Jewish Concepts of Divine Oneness

Summary

This book offers a selective, typological overview of Jewish perspectives on the belief in God's oneness. To achieve this, the author divides the history of Judaism into four phases - biblical, rabbinic, medieval, and modern - and presents diverse models for understanding the reality of divine oneness within each phase. These models not only offers insight into different perspectives on the topic but also illuminate diverse layers of polemical discourse in the Jewish tradition, whether internal or in dialogue with other religions and worldviews. In addition, the author invites readers to consider how to think about the plurality of the perspectives at hand, and if and how such meta-reflection can enrich the lives of contemporary readers, Jewish and non-Jewish alike. No prior knowledge of Judaism is necessary.

Introduction: “One God, Two Jews, Three Opinions”

No Jews would dispute the fundamental importance of belief in God’s oneness within their religion. To illustrate this point, your Jewish neighbor might cite for you the opening line of the Shema – the Jewish “confession of faith” comprising three biblical passages (Deut 6:4–9; 11:13–21; Num 15:37–41) – which begins with a clear affirmation of divine oneness: “Listen, Israel: the Lord is our God, the Lord is one.” Or another Jewish passerby might refer you to the Decalogue – the quintessence of Jewish Law – which includes the commandment to worship no other gods: “You shall have no other gods besides Me” (Exod 20:3). Yet, when you ask them of the content of this oneness, you will readily find that there is virtually no consensus. As the saying goes: “Ask two Jews, and you’ll get three opinions.”

The belief in God’s oneness as the cornerstone of Judaism cannot be defined according to its essence, because it is a fluid concept that changes over the course of history. Even a cursory glance at classical literature reveals a vast spectrum of diverse and at times conflicting accounts of the divinity, including biblical and rabbinic descriptions of a personal God, Maimonides’ discussion of the Aristotelian Unmoved Mover, and the Kabbalistic understanding of divine reality as a dynamic organism with varied aspects or sefirot – to name but a few of the approaches discussed later. These descriptions of divine reality share few commonalities, aside from the fact that they all purport to be the authentic reading of the Jewish Scriptures. What underlies this diversity is a simple fact: Different religious sensitivities give rise to different models for understanding and experiencing divine reality; and accordingly, what remains constant in the Jewish tradition is not a shared understanding of God’s oneness but a shared commitment to the reality of that oneness – whatever its content may be.

I will revisit this conceptual diversity later in the Element and explore its existential and normative implications. However, before delving into that discussion, it is essential to delineate the diversity itself. I will begin by dividing Jewish history into four phases – biblical, rabbinic, medieval, and modern – and discuss some of the corresponding models for understanding the reality of divine oneness within each phase.

Above all, I urge you to keep in mind the following crucial point as you read this Element: Judaism, like many other world religions, can be understood in two different ways. One viewpoint sees it as a unified system comprising a coherent ideology with a set of practical norms. Within this framework, there is a notion of a more genuine version of Judaism, alongside deviant and erroneous variations. Alternatively, Judaism can be seen as an ongoing conversation among competing views about the teaching and practice set forth purportedly by its founder, Moses. Adopting this approach allows for an appreciation of the inherent plurality of outlooks (cf. Hartman 1999; Sagi 2007). The choice between these alternatives not only shapes our approach to the varieties of religious experience and perspective discussed in this Element but also, as I will explain later, influences the extent to which we can have a genuine encounter with the other, human or divine.

Four remarks must be made before proceeding further: First, my primary aims are to tell a conceptual story of the Jewish belief in divine oneness, and thereby to outline the landscape of competing views of the subject as they have emerged in the course of history. In this regard, the nature of my analysis is typological rather than strictly chronological; at times, I depart from historical sequence for heuristic purposes.

Second, due to constraints of length, the Element cannot delve deeply into every significant issue. Each perspective discussed in this Element deserves a thorough examination in a full-length monograph, which is unfeasible in this shorter format. Some readers may also believe that it ought to have included one issue or another that went unmentioned. However, this Element does not aim to provide a comprehensive overview of the theme of divine oneness in Jewish tradition. Instead, its purpose is to foster informed discussions and reflections on the complexity, profundity, and internal diversity of the subject. I would consider my goal achieved – and say dayenu (“done enough!”) – if I have made this intricate yet fascinating theme accessible to beginners while also inspiring interested readers to explore the topic further.

Third, some readers may perceive the scope of discussion as simultaneously too narrow and too broad. Too narrow – because its subject is not Jewish theology in its entirety but rather limited to one specific category, namely, divine oneness. Too broad – because I will discuss this category not in isolation but in relation to a network of related concepts and experiences. Expanding this horizon is essential, as the full significance and depth of the subject might otherwise not be appreciated.

The fourth and final preliminary remark is for the beginner: The word “Torah” (lit., instruction, guidance, or teaching) can bear multiple meanings. It can signify, in its most limited sense, the first section of the Hebrew Bible – also known as the Five Books of Moses or Pentateuch (i.e., Genesis, Exodus, Leviticus, Numbers, and Deuteronomy). Alternatively, in a broader sense, it encompasses the entire corpus of sacred literature or the whole body of religious teachings and precepts in Judaism. The meaning of the term should be self-explanatory from the immediate context in which it appears.

Biblical Phase

The Hebrew Bible is a literary anthology of writings that were produced in ancient Israel, a canon that Jews and Christians traditionally believe contains revealed teachings. As a record of God’s eternal covenant with the people of Israel, it traces their formative period within a broader spectrum, from the creation of the world up to the restoration of Zion after the Babylonian exile. This anthology as a whole can thus be viewed as presenting a cosmic drama, whose protagonists are God and humans, and whose focus is the interpersonal relationship between the two. Within this spectrum, the biblical story of God’s covenant with Israel unfolds.

Despite scholarly efforts, we do not know exactly how or when the biblical texts were selected and codified as Jewish scripture. However, we do know that by the fifth-century bce, the first five books of the Bible were canonized as the Torah, while by the second-century ce, all other books were deemed sacred and canonical. In any case, the Hebrew Bible has always been foundational to Judaism, making it logical to start our inquiry into the Jewish understandings of divine oneness with this text.

Before proceeding, it is important to note three caveats. Firstly, when discussing the religion of ancient Israel, it is crucial to distinguish two types of religion: “biblical religion” and “ancient Israelite religions” (Dever 2001; Sommer 2009: 145–174). Biblical religion refers to the religion prescribed in the Hebrew Bible, with its internal diversity, while ancient Israelite religions encompass a broader range of religious beliefs and practices existing alongside biblical religion in antiquity. For example, archaeological findings suggest that some ancient Israelites believed their deity (YHWH) had a female consort, a fertility goddess called Asherah. In contrast, while some biblical texts hint at or preserve traces of this belief, none of their authors seem to have endorsed it (Weinfeld 1996; Sommer 2009: 44–49, 155–159). Be that as it may, there is no scholarly consensus regarding the exact relationship between these two kinds of religion – some arguing for their essential congruence, whereas others for a lack thereof (cf. Greenstein 1997; Geller 2000; Sperling 2020). I have therefore limited the scope of this section to biblical religion.

Secondly, biblical literature is a culmination of contributions from multiple authors spanning over a millennium. While all its books acknowledge the supremacy and incomparability of the biblical God, they also display varying theological outlooks. Again, there is no scholarly consensus here – some emphasize their essential consistency, while others highlight their polyphonic nature (cf. Goldingay 1987; Geller 1996; Schwartz 1996; Knohl 2003; Carasik 2014). Additionally, since some of the wisdom texts (e.g., Proverbs and Ecclesiastes) place little emphasis on God’s direct intervention in human life and history, several critics have attempted to identify naturalistic, impersonal concepts of God in those texts, which significantly diverge from the rest of the Hebrew Bible. However, given that the biblical wisdom tradition is also theistic, I find such a hypothesis untenable. All in all, I have avoided the intricacies of these and other contested subjects, focusing instead on general issues.

Finally, various scholarly efforts have been made to explain the origins of biblical religion. I, for one, concur with the view that empirical inquiry cannot, and indeed need not, address this topic – or any inquiry concerning the veracity of revelatory claims – given its inability to penetrate into what lies behind the ultimate nexus of reality. In other words, empirical research is better suited to examining the history and phenomenology of biblical religion subsequent to its inception (Jindo 2012: 239–241; Sommer 2017: 216–218).

In what follows, I will first delineate some of the constitutive categories of biblical religion – namely, divinity, humanity, sin and evil, divine kingship, and the universe. Afterward, I will delve more specifically into the theme of divine oneness.

God’s Name and Gender

The term “God” typically translates various Hebrew words such as ’el, ’eloah, or ’elohim, likely stemming from the root ’yl or ’wl, meaning “to be powerful.” Most frequently, the Hebrew Bible spells the proper name of the God of Israel with the Hebrew letters, yod-heh-vav-heh, commonly referred to as the Tetragrammaton, meaning “four letters” in Greek. This name is believed to originate from the verb h-v-h, meaning “to be,” with the masculine subject prefix y-; however, its exact meaning remains unknown (one interpretation suggests understanding it causatively as “the one who brings into being”). Conventionally, the Tetragrammaton remains unpronounced – probably vocalized as Yahweh – and is often spelled as YHWH or Lord (Ben-Sasson 2019; Lobel 2021: 91–125).

Biblical Hebrew, like other Semitic languages, employs gendered nouns, categorizing them as either feminine or masculine, unlike Biblical Greek, which includes a “neuter” gender. Correspondingly, verbs in Biblical Hebrew are conjugated based on the gender they govern. YHWH, the God of the Hebrew Bible, is consistently portrayed in the masculine gender, often depicted with human male attributes, such as king, father, warrior, and husband, although there are exceptions (cf. Isa 42:14; 49:15; Gruber 1992: 1–15). However, the interpretation of this gendered language remains open to debate, as it is uncertain whether it signifies something about God’s essence or merely reflects the roles attributed to God.

Some argue that since both male and female humans are created in God’s image and likeness (Gen 1:27; 5:1–2), the biblical God embodies both sexes. Others contend that the biblical God transcends the category of sex and gender altogether, suggesting that YHWH is sexless (cf. Frymer-Kensky 1992). As discussed later in the Element, both the bisexual and asexual perspectives on divinity are extensively elaborated upon in the medieval phase – the former in certain kabbalistic trends, while the latter in their philosophical counterparts.

Absolute Freedom and Personhood of the Biblical God

The Hebrew Bible opens with a creation account, which establishes the relationship between God and the universe. In this biblical narrative, creation is depicted as an act of bringing order to the cosmos, rather than production of matter out of nothing – a concept known as creatio ex nihilo, which emerged later. Through the triumph over chaotic forces, creation establishes a cosmic space where the divine and the human can cohabit. However, biblical authors do not view this victory as final, as they often attribute undeserved evil to the persistence and resurgence of such forces. Nevertheless, prophets envision that the ultimate triumph will one day prevail (Isa 25:6–8; 27:1; 51:9–11; Levenson 1994).

Equally significant, the opening creation story (Gen 1:1–2:4a) articulates fundamental postulates of biblical religion. It emphasizes that the world we inhabit is a purposeful creation of the one supreme deity, and that natural phenomena – such as heaven, earth, sea, sky, and luminaries – are not divinities themselves but rather components of the manifold works of the creator deity. This perspective secularizes nature, rejecting immanent concepts of divinity prevalent among neighboring cultures (Berger 1967: 105–126).

This clear distinction between YHWH and nature should not be mistaken – as is often the case – with the notion of ontological separation, which suggests that any interaction between YHWH and the world is logically impossible. Instead, the distinction should be understood in terms of absolute freedom: that this deity is not restricted by primordial nature or any other forces, metaphysical or otherwise. Thus, biblical religion can acknowledge the existence of other celestial entities to the extent that their existence does not compromise YHWH’s absolute freedom (e.g., Exod 15:11; Deut 10:17; Mic 4:5; Ps 29:1–2). Overall, what characterizes biblical religion is the qualitative (rather than the numerical) oneness of this deity: the absolute supremacy of YHWH as the one and only (Kaufmann 2017a [1937]; Sommer 2017). This concept of a singular supreme deity who transcends fate and nature forms a basis for divine interpersonality, arguably the defining uniqueness of biblical religion: that a deity who controls nature – including the deity’s own nature – alone can freely and continually engage in an interpersonal drama with humankind (Muffs 2005: esp. 55–60). As succinctly stated: “Judaism conquered nature and put in its place the personality that revealed itself in an act of love. Everything that formerly had a natural quality to it took on, in Judaism, a personalistic cast. The cosmic sphere is now personal, moral, communicative, and loving” (Muffs 1992: 45).

The abstract conception of the biblical God as devoid of form and personality – often encountered in the contemporary discourse of biblical theology – is ultimately of Greek origin and therefore extrinsic to biblical religion (Kaufmann 2017a). The biblical God is consistently experienced and understood as a relational subject, always portrayed as the living God rather than an abstract principle or process. Consequently, philosophical categories of perfect being, such as “first cause” or “pure being,” fail to adequately capture the reality of this deity. Indeed, these categories lack life and responsiveness, and insofar as relationships are concerned, they are deficient and imperfect. Similarly, the theological concept of “divine simplicity” is foreign to biblical religion, as the biblical deity exhibits a multifaceted personality expressed through the drama of interpersonal relationships (Heschel 1996: 267–285; cf. also Wyschogrod 1989: 82–124; Jaffee 2001). It is no surprise, then, that biblical authors use narrative – rather than propositional statements – as a main medium for portraying the divine relationship to human personalities. For no other mode of communication can better capture the complexity of such interpersonal and intrapersonal dynamics than storytelling (Talmon 1988; Muffs 2005: esp. 97–102). It is also worth noting that making God’s image is prohibited in the Bible not because God is invisible or incorporeal, but rather because any representation is unworthy of God and also inimical to substituting a symbol for what it represents (Halbertal and Margalit 1992: 45–48).

God’s Antagonist: The Human Being

In the biblical worldview, where there are no celestial rivals and meta-divine forces that limit divine will, only one creature retains the ability to challenge the authority of God: humanity. Human beings stand before God not as a force that can constrain the divine reality, but rather as a personality that engage God in the complex normative and psychological relationships. Much of the biblical cosmic drama revolves around this tension between divine and human agency (Muffs 1992: 9–48; Muffs 2005; cf. also Halbertal and Margalit 1992: 68–73; Kaufmann 2017a [1937]: 310).

In this respect, the early history of humankind can be read as a story about normative development. Initially, the first humans possess the capacity to obey or disobey God’s commands. However, akin to toddlers or children, they lack the ability to discern whether a particular action is inherently good or evil. By eating from the tree of knowledge of good and evil, Adam and Eve gain the capacity to make normative choices on their own – without relying solely on God as the exclusive arbiter in normative matters (Wyschogrod 1986). At stake is the acquisition of moral independence akin to puberty, an irreversible process. Biblical literature thus invites readers to reflect if and how humans, including readers themselves, can develop an optimal relationship with the sense of autonomy and normative agency they have acquired, thereby fulfilling their own telos.

Human freedom, in turn, is facilitated by two types of divine acts: self-adjustment and self-limitation. The first act acknowledges human fallibility and adjusts, when necessary, the standards of expectation. In simpler terms, God adapts to the knowledge gained about humans, who are God’s own making. A clear example is found in the epilogue to the Flood narrative, where God acknowledges the inherent evil inclination in the human heart (Gen 8:21) and modifies the earlier command of a vegetarian (or frugivore) diet, permitting meat consumption as a partial concession (Gen 9:3–4; cf. 1:29–30). As for God’s act of self-limitation, it is vital not only for humans to actualize their potential – because personality cannot function without freedom – but also for divine sovereignty to be authentic. Otherwise, coerced reverence and subsequent obedience would undermine God’s authenticity as cosmic sovereign.

Sin and Evil

Biblical literature exhibits a tendency to conceive of sin and evil as a consequence of human freedom. If the world operates according to the absolute will of a moral and just deity, the problem of evil is inescapable. In this regard, the book of Genesis attributes all the basic evils – natural (e.g., death, pain, and toil), moral (e.g., murder and violence), and religious (e.g., impiety and idolatry) – to human responsibility, that is, to the primordial inclination of humans to aspire for autonomy and overcome their creaturely status (Kaufmann 1960: 292–295). What involves this aspiration is not merely a problem of self-deification (seeking to be like God) but, more fundamentally, the eclipse of God (seeking independence from, and perhaps replacing, God). As astutely stated: “The inner meaning of sin [in this primeval narrative] is not simply an act of disobedience against God but an attempt to overthrow God by making man into a God-like creature” (Wyschogrod 1986: 106).

In biblical thinking, sin and moral evil derive from a lack of true knowledge of God, often referred to as the “fear of God” (yir’at ’elohim) by biblical authors. This fear, or reverence, arises from a profound recognition that humans are objects of divine attention, and that the ultimate source of their norms and existence is not themselves, but the divine sovereign (Jindo 2011). This recognition sets fundamental standards of behavior, even in situations where no legal sanction is enforceable. The presence of this fear deters individuals from committing interpersonal wrongs, including murder (Exod 1:17, 21), adultery (Gen 39:9), exploitation of the vulnerable (Deut 25:18), betrayal of trust, or abuse of authority (Gen 42:18). Conversely, its absence may embolden individuals to engage in such transgressions (Gen 20:11; Deut 25:18). Because this attribute involves a deep understanding and close relationship with divinity, its semantic equivalents include such terms as “knowledge of God” (Prov 2:5; 9:10) and “loving God” (Deut 10:12).

Humans are expected to know such basic standards of conduct on their own, just as Cain (Gen 4) and the generation of the Flood (Gen 6–9) are held responsible for their acts of misconduct, without prior warning from God. In biblical thinking, only in the eschatological time will non-Israelites fully grasp the vanity of idolatry and acknowledge the supremacy of YHWH. Until then, Israel alone is held guilty for idolatry, whereas other peoples are generally judged for violating basic standards of conduct rather than for idolatry itself (Kaufmann 1960, 74–76, 386–388, 424–425; Tigay 1996, 435–446).

Strikingly enough, biblical texts recognize the existence of celestial beings that can entice humans into sin (e.g., Gen 3:1–5; 1 Kgs 22:19–23; Job 1–2; cf. Deut 13:4 [v 3 in Heb]). If individuals succumb to such temptations, they are accountable for their actions. The underlying idea is that humans possess not only moral agency but also the capacity to cultivate personal traits whereby they can resist such enticements and inner impulses (Gen 4:7).

As biblical religion tends to attribute misfortunes to human responsibility, it can promote a belief that the suffering must be a consequence of sin. Accordingly, any conflict between the notion of a just order and the reality of individual suffering might readily be dismissed as illusory. However, the Book of Job – the biblical tale of innocent suffering – serves as a corrective to this tendency (along with many of the crisis psalms in the Psalter; cf. Westermann 1987: 259–280; Brueggemann 1995: 98–111). Not only does the Book of Job reject the practice of blaming the innocent sufferer to resolve the problem of evil, but it also exposes the injustice inherent in theodicy, which transfers responsibility from God to the human victim (Glatzer 1969; Greenstein 2009).

Divine Kingship

Biblical authors comprehend the operation and meaning of reality, more often than not, through a complex paradigm of divine kingship. YHWH is conceived of as king, the heavenly council as royal court, the universe as dominion, and humans as subjects.

The convention of apprehending the cosmos as a state is not unique to biblical religion; we can find the same mode of conceptualization in its neighboring polytheistic religions. The difference between the religious systems lies in the specific political model through which they perceive the operation of the world, namely, an oligarchic versus an autocratic model (cf. also the comparison between the British cabinet and the American cabinet discussed in Sommer 2009: 163). The polytheistic mind perceives a plurality of divine wills behind the operation of the world, whereas the biblical mind recognizes the supreme and ultimate will of a single deity behind it.

Within this royal framework, YHWH as divine overlord establishes a covenantal relationship with the people of Israel as vassals. They are called to be a model nation for all humankind, demonstrating the divine reward bestowed on those who walk in YHWH’s way and acknowledge this deity’s authority (Gen 12:1–3).

This royal paradigm involves a systematic correspondence between two frames of reference: that of kingship and that of the cosmos (Jindo 2014). The basic correspondences of the two frames can be presented as in Figure 1.

Figure 1 Royal paradigm: understanding reality in biblical context

Scholars are divided in their opinions as to the nature of this royal model. Many critics identify it as a metaphor – as the projection of a human institution onto the celestial and cosmic sphere to facilitate understanding of the divine workings, or to provide societal order and structure. However, some scholars disagree with this interpretation, pointing out that the Bible depicts God as actually reigning over Israel and the universe. While metaphors may be involved in the depiction, the notion of divine kingship itself is not a metaphor: God is literally king. In fact, interpreting this royal paradigm as a metaphor would undermine the objections raised by figures like Gideon and Samuel against the establishment of human kingship, as depicted in Judges 8:23 and 1 Samuel 12:12, respectively. This is because there would otherwise be no real conflict between divine and human kingships.

For biblical authors, furthermore, divine kingship – and Israel’s covenantal relationship to the divine King – not only constituted an objective reality but also formed the entire meaning and structure of their lives as Israelites. In biblical thinking, it follows, divine kingship was not an imaginative possibility but an ontological necessity: In other words, biblical authors were not only unable to doubt its reality but also unable to conceive of their existence as Israel outside of this reality.

Political Idolatry

Political authority is prone to the sin of idolatry, particularly when it demands absolute loyalty from its citizens to the extent of self-deification. This action violates the biblical prohibition: “You shall not have other gods beside Me” (Exod 20:3; Deut 5:7). To this day, some people prefer not to swear allegiance but instead to declare an oath of loyalty to a secular state. They refrain from ascribing absolute value to any human system or symbol of rule or treating it as an object of worship (others may avoid swearing due to religious beliefs prohibiting the act itself; cf. Exod 20:7; Deut 5:11).

With respect to the institution of human kingship, the biblical canon is not unanimous (Halbertal 2007; Lorberbaum 2010: 1–36). Some passages present a rigid, exclusive perspective, viewing human kingship as a form of deification (e.g., Judg 8:23 and 1 Sam 8:7–8, as mentioned earlier), whereas other passages offer a more moderate, practical view, suggesting that the institution of kingship itself does not constitute idolatry as long as it remains within its bounds (Deut 17:14–20; 1 Sam 12–15).

The matter becomes more complex when considering foreign authority. Since YHWH is Israel’s protector and sovereign, entering into protective treaties with superpowers such as Egypt or Assyria might be seen as a form of idolatry (e.g., Isa 31:1; Jer 2:18, 36; Ezek 16 and 23; Hos 7:11–13). However, YHWH is also said to elect foreign emperors, such as the Babylonian king Nebuchadnezzar or the Persian king Cyrus, to subdue nations and fulfill a divine plan, thereby prompting Israel to accept the authority of these rulers (Isa 45:1–13; Jer 21:3–10; 27:5–22).

The Shema (Deut 6:4)

All this explains how (or better yet: how not) to understand what is often regarded as a catechism of Judaism – namely, Deuteronomy 6:4 and its last four Hebrew words – yhvh ’eloheinu yhvh ’eḥad, which literally means: “YHWH our God YHWH one.”

This utterance has, at least, three interpretive conundrums:

1. (1) The exact meaning of ’eḥad (lit., one) is ambiguous – should it be understood as describing God’s nature (i.e., that God is “one”) or to express exclusive allegiance to God (i.e., that Israel’s God is YHWH “[al]one”)?

2. (2) Because the Hebrew language lacks a present-tense verb like “is” to link subject and predicate, there are various possibilities for inserting this verb when translating the phrase (e.g., “YHWH [is] our God, YHWH [is] one”; “YHWH [is] our God, YHWH [al]one”).

3. (3) It is not certain whether the phrase, taken by itself, forms a single clause (e.g., “YHWH, our God, is one”) or consists of two separate clauses (e.g., “YHWH is our God; YHWH is one”).

These ambiguities have led to various interpretations of the phrase. Some of the most common translations include:

1. A. YHWH is our God, YHWH alone (cf. NJPS, NRSV)

2. B. YHWH our God, YHWH is one (cf. OJPS, NKJV)

3. C. YHWH our God is one YHWH (cf. KJV; RSV)

The first rendering takes the utterance as a statement about relationship, emphasizing Israel’s exclusive loyalty to YHWH (stating that YHWH “alone” must be recognized as Israel’s God; for this sense of “one,” see 1 Chr 29:1). The second rendering understands the utterance as a statement about God’s nature, either in terms of “unity/indivisibility” (indicating that YHWH does not consist of multiple independent entities; for this sense of “one,” see Exod 36:13) or in terms of “uniqueness/incomparability” (asserting that YHWH is “one and only”; for this meaning of “one,” see Song 6:9). The third reading regards the utterance as a statement about sameness, declaring unity in face of the multiplicity of different traditions and sanctuaries of YHWH (affirming that there are not many YHWHs; for “one” in the sense of “same,” see Gen 11:1). Overall, the verse neither denies nor confirms the existence of other deities (for more on Deut 6:4, see Tigay 1996: 438–441; Geller 2000: 290–302; Sommer 2009: 220–222).

Biblical Views on the Nature, Origin, and Future of Polytheism

How did biblical authors understand the nature and origin of the worship of idols and celestial beings, practiced by other peoples and, at times, by some of their own?

As for the nature of such practice, we can discern two different views in biblical literature: one regarding the objects of worship as (1) effective entities and the other as (2) ineffective nonentities. The first view understands idolatry to be a category mistake, regarding a supernatural entity that is subordinate to and dependent on YHWH – be it an angel, spirit, or any other celestial being – as supreme and independent. The forbidden practices of invoking occult powers (Deut 18:9–12; 1 Sam 28), references to angelic patrons of Persia and Greece in Daniel (10:21), and prophecies like Isaiah’s of YHWH punishing the “host of the high heaven on high” (Isa 24:21) align with this understanding. Conversely, the second view regards idol worship as a form of fetishism or metaphysical mistake, wherein reverence is directed toward images devoid of independent living powers (2 Kgs 19:17–18; Isa 44:9–20).

As regards the origin of polytheism, while modern critics often assume that biblical religion emerged from polytheistic backgrounds, biblical tradition offers a contrasting perspective: The earliest generations of humanity, including Adam, Eve, Cain, and Abel, initially worshiped the one God. The practice of idol worship and reverence for celestial beings, including the heavenly bodies, emerged later, either during or after the dispersal of humankind and the confusion of languages – while the faith and worship of the one God was maintained by Abraham and his descendants. A variant (and presumably original) reading of Deuteronomy 32:8–9, found in one of the Qumran scrolls and the Septuagint, supports this understanding. It states: “When the Most High allotted the nations and set the divisions of humankind, the boundaries of peoples were fixed equal to the number of divine beings. For YHWH’s portion is this people; Jacob, God’s own allotment” (for more on this, see Tigay 1996: 435–436, 513–515).

With respect to the future of polytheism, biblical prophets envision a time when other nations will return to the true knowledge of the one God (most distinctly, Zech 14:9). However, there exists a divergence of opinions regarding whether these nations will completely abandon their own religious traditions. For instance, consider the vision of hope in Isaiah and Micah, where both texts use almost identical language to describe the future era with one crucial difference – the concluding verse:

Isaiah 2: 2In the days to come, the Mount of YHWH’s House shall stand firm above the mountains and tower above the hills; and all the nations shall gaze on it with joy. 3And the many peoples shall go and say: “Come, Let us go up to the Mount of YHWH, to the House of the God of Jacob; that we may be instructed in God’s ways, and that we may walk in God’s paths.” For instruction shall come forth from Zion, the word of YHWH from Jerusalem. 4Thus God will judge among the nations and arbitrate for the many peoples, and they shall beat their swords into plowshares and their spears into pruning hooks. Nation shall not take up sword against nation; they shall never again know war. 5O House of Jacob! Come, let us walk by the light of YHWH.

Micah 4: 1In the days to come, the Mount of YHWH’s House shall stand firm above the mountains and it shall tower above the hills. The peoples shall gaze on it with joy, 2And the many nations shall go and shall say: “Come, Let us go up to the Mount of YHWH, to the House of the God of Jacob; that we may be instructed in God’s ways, and that we may walk in God’s paths.” For instruction shall come forth from Zion, the word of YHWH from Jerusalem. 3Thus God will judge among the many peoples, and arbitrate for the multitude of nations, however distant; and they shall beat their swords into plowshares and their spears into pruning hooks. Nation shall not take up sword against nation; they shall never again know war … . 5Though all the peoples walk each in the names of its gods, we will walk in the name of YHWH our God forever and ever.

By comparing the closing verse of each passage, it becomes apparent that the two prophets hold differing views on the future of polytheism. Isaiah, who elsewhere envisions even the conversion of the world’s great powers of his day, Assyria and Egypt, to worship YHWH (19:23–25), appears to anticipate the complete abandonment of polytheism. He foresees nations renouncing their trust in foreign deities or human handiwork and instead choosing to “walk by the light of YHWH” alone. In contrast, Micah predicts that while all peoples will acknowledge the supremacy of YHWH, they will continue to maintain their own worship and religious traditions, each people walking “in the names of its gods” (for more on the two prophets, see Uffenheimer 1994).

*

While there is much more to discuss regarding biblical categories relevant to divine oneness – such as the rise of angelology and the motif of Lady Wisdom in Proverbs 8 – I must omit them due to space constraints. Still, I will address at least some of them later in due course.

Rabbinic Phase

Historically speaking, the rabbinic phase extends approximately from the second- or first-century bce to the seventh-century ce. This period spans from the era of Hellenistic dominance over the land of Israel to just before the rise and spread of Islam in the Middle East. It marks the formative period of rabbinic Judaism, and, accordingly, its impact on the later phases of Jewish tradition – in terms of both the normative canon it produced and the religious sensibilities it introduced – is decisive (Urbach 1975).

Rabbinic Judaism emerged, in part, in response to the destruction of the Jerusalem Temple in 70 ce, grappling with the challenge of sustaining intensive religious life without a shared spatial center of Jewish existence. It elevated Torah study to the core of Jewish life, transforming into a tradition centered around textual interpretation (Halbertal 1997). Although traces of this text-centeredness can be found in the biblical phase (Fishbane 1985; Sommer 1998), the rabbinic sages made a significant stride in redefining Judaism as a text culture. Moreover, these sages, like some of their biblical predecessors, viewed scripture not only as a record of past revelations but also as a locus of ongoing revelation. Thus, every new understanding they gleaned from the text was regarded as a moment of divine disclosure. This notion of revelation facilitated the existence of a religious community independent of physical location – whether in the Jewish homeland under a foreign authority or in the Diaspora. Concomitantly, sages well versed in scriptural hermeneutics and religious precepts emerged as the primary religious authorities, superseding the priests and prophets who held sway in the biblical period. Those sages also developed a comprehensive system of Jewish law that would determine every aspect of Jewish life (Urbach 1986).

The teachings and stories of the sages from this era are preserved and transmitted in what is commonly known as “rabbinic literature.” The term encompasses a variety of polyphonic compositions that initially existed as oral tradition. Among these compositions are the Mishnah, a compilation of oral law and diverse opinions, and the two major collections of rabbinic teachings based on the Mishnah: the Jerusalem Talmud and the Babylonian Talmud. Additionally, there are homiletic expansions of the Bible known as Midrashim (the plural form of Midrash). Traditionally, the entire body of rabbinic literature is considered the “Oral Torah,” which, as an indispensable companion to the “Written Torah” (the Five Books of Moses), is believed to have originated from the revelation at Sinai.

I will first describe rabbinic concepts of God in general. Following that, I will address two issues related to divine oneness – one theological, the other political – that highlight distinct sensitivities and concerns of the rabbinic phase.

The Rabbinic God as a Relational Subject

On the whole, the sages of rabbinic Judaism embraced the biblical understanding of God as a relational subject without reservation. They freely employed a diverse array of human analogies – depicting God as king, parent, judge, shepherd, or teacher – to elucidate the reality of God. In so doing, they believed they neither compromised the sublime nature of God nor violated the biblical injunction against creating graven images of divinity (Goshen-Gottstein 1994; Lorberbaum 2015; Kaufmann 2017a).

Indeed, the idea of divine incorporeality, which intrigued medieval philosophers, arose later than both the biblical and rabbinic periods. From Saadia Gaon in the tenth-century ce to scholars of the nineteenth and twentieth centuries, Jewish thinkers often sought to demonstrate rabbinic rejection of anthropomorphism by citing certain tendencies in Aramaic translations of the Bible from the rabbinic era – such as substituting God’s name or pronoun with such terms as memra “word,” shekhinta “divine presence,” and yikra “glory.” However, these tendencies were not necessarily anti-anthropomorphic. Instead, they aimed to emphasize God’s sublimity rather than incorporeality (Klein 1981). As discussed toward the end of this section, one notable exception is Hellenistic Jewish philosopher Philo (c. 20 bce–50 ce), who resided in Alexandria, Egypt, and sought to merge the Jewish and Greek cultures. Overall, in Jewish history, the question of divine personality – whether conceiving of God as a personality might diminish the uniqueness and transcendence of the divine – was not a concern until the influence of Greek philosophy began to emerge (Kaufmann 2017a).

The following biblical verse exemplifies how rabbinic sages understood the reality of the divine, and how their concerns were different from the metaphysical inquiries that occupied medieval Jewish philosophers (this example was pointed out to me by Moshe Halbertal; see Halbertal 2022):

And YHWH went before them by day in a pillar of cloud to guide them, and by night in a pillar of fire to give them light, so that they might travel by day and by night.

(Exod 13: 21)

Both rabbinic sages and medieval thinkers discussed how to understand this depiction of God traveling ahead of the Israelites after the exodus from Egypt. For medieval philosophers, the verse posed a metaphysical question: How could the reality of a divinity transcending time and space manifest as a pillar of smoke by day and a pillar of fire by night, guiding the Israelites in the wilderness? For example, Abraham Ibn Ezra (1089–1167), a prominent medieval biblical exegete, suggested: “Scripture speaks in human language – God’s power went with Israel, as in ‘Whose glorious arm was made to march at the right hand of Moses’ (Isa 63:12).” Ibn Ezra resolved the metaphysical puzzle by proposing that what led the Israelites was not the reality of God itself but rather an intermediary being – “God’s power” – that mediates divine transcendence and the empirical world. However, for the rabbinic sages, their concern lied elsewhere. Consider the following midrashic passage:

“And YHWH went before them by day in a pillar of cloud to guide them, and by night in a pillar of fire to give them light, so that they might travel by day and by night” (Exod 13: 21). Can this be said? Is it not written “Do I not fill both heaven and earth?—declares YHWH”? (Jer 23:24)? … Rabbi said: [Here is an analogy that explains the issue: The emperor] Antoninus would sometimes continue his court sessions, sitting on the platform till after dark, and his children would stay after dark with him. After he left the platform, he would take the torch and light [the way] before his children. The nobles close to him said: We will take the torch and light [the way] before your children. But he would say to them: “It is not because I have no one to take the torch and light [the way] before my children; but see, I show the love for my children, so that you will treat them with respect.” So, God showed the love of Israel to all the nations of the world … .

Mekhilta d’Rabbi Ishmael, Va-Yeḥi, Ptiḥta

The parable of Antoninus clarifies that what concerned the sages was not the how of metaphysical possibility, but rather the why of relational propriety – namely, why does God choose to appear in ways that seem inappropriate for God’s sublime dignity? The sages understood this choice to be an expression of divine love and intimacy with Israel.

The case at hand thus exemplifies that the rabbinic God may be characterized as awesome, eternal, almighty, righteous, good, and loving, but neither incorporeal nor impersonal (for more on this, see Kaufmann 2017a; cf. Weiss 2016: esp. 149–160; Halbertal 2022).

Idol Worship in the Rabbinic Phase

Like biblical authors, the rabbinic sages were vigilant against anything that could be perceived as having its own authority and thus deserving worship on its own merits. The existence of such a being could undermine the exclusive demand for service to God and also compromise the absolute uniqueness of God as the one and only (Urbach 1975: 19–36).

The prevailing view among the rabbinic sages was that the desire for idol worship, a major issue in the biblical period, had already disappeared from Israel by their time (TB Yoma 69b; Avodah Zarah 17a–b). The images and idols of foreign deities had ceased to be real enemies by then. True, from the late third-century bce onwards, when the land of Israel was dominated by Greek rule and Hellenization, which, in turn, introduced its idols and cults to the area, there were repeated attempts by locals to eradicate idolatry from the land – most notably, the Maccabean Revolt (167 bce–160 bce). This uprising abolished, among other things, the worship of foreign idols introduced into the Jerusalem Temple. Nevertheless, it remains unclear whether the primary concern of those insurgents lay in the idolatrous worship itself or rather in what its imposition upon the locals and their land symbolized: the humiliating loss of their political and religious autonomy (Schwartz 2022: 51–58).

Be that as it may, the temptation of idol worship was no longer a real concern in the rabbinic period. Instead, the sages considered two issues as cardinal threats to belief in God’s oneness – “binitarian thought” and “political idolatry.”

Binitarian Thought in Second Temple Judaism

“Binitarian” refers to a belief that divinity exists as two figures, similar to the “trinitarian” doctrine of Christianity, which asserts that divinity exists as three persons – Father, Son, and Holy Spirit. The question to address is whether and to what extent binitarian thought is actually involved in the rabbinic concepts of divinity. This subject should be better explored within the broader context of a distinct phenomenon identifiable in the transitionary stage between the biblical and the rabbinic period – namely, the rise of angelology (Urbach 1975: 135–183; Melvin 2013).

The Babylonian exile appears to have had a considerable impact on Jewish angelology, as indicated in rabbinic tradition, which suggests that “the names of the angels were brought by the Jews from Babylonia” (JT Rosh HaShanah 1.2, 56d; Genesis Rabbah 48). Within this worldview, the divine realm was conceived as an intricate bureaucratic system – not unlike the Babylonian system of upper and lower spirits – wherein celestial beings were perceived with a notable degree of individual identity, bearing specific names and occupying different ranks. The sublime character of God seemingly necessitated the presence of such beings to mediate between God and the world. In fact, from the Babylonian exile and onwards, it was often “the angel that talked with me,” rather than God, who directly communicated with the prophet (Zech 1:9, 14). The concepts of angelology underwent further development in postbiblical apocalyptic literature, as evident in such texts as 1, 2, and 3 Enoch, Jubilees, and the Testaments of the Twelve Patriarchs. This postbiblical world of angels also includes rebellious angels and demonic spirits. Historically speaking, however, it remains unclear how many of these and other angelic concepts already existed, perhaps in esoteric form, in biblical times, and how many of them were newly developed thereafter – or, put differently, how much of them were the result of internal development and how much of them should be ascribed to external factors, such as Magian and Zoroastrian influence.

The presence of celestial beings who directly interact with humans has the potential to undermine God’s exclusive claims on human allegiance and worship. This is because such celestial beings may overshadow God’s reality and, in turn, inspire their own cult. The issue becomes more complex when it involves binitarian ideas or instances where God awards a celestial figure a throne, elevating it to a rank as lofty as God’s own. This subject is referred to in rabbinic idioms as “two powers [in heaven].”

The motif of a prominent or primordial figure enthroned or abiding next to God can be traced back to biblical literature, for example, in the vision of judgment in Daniel 7:9–14.

⁹As I watched, thrones were set in place, and an Ancient of Days took a seat – with a garment like white snow, and hair like lamb’s wool… . ¹⁰… Thousands upon thousands rendered service; myriads upon myriads stood in attendance… . ¹³As I watched in the night visions, I saw one like a human being coming with the clouds of heaven. He came to the Ancient One and was given an audience. ¹⁴Dominion, glory, and kingship were given to him; all peoples, nations, and languages should serve him. His dominion is an everlasting dominion that shall not pass away, and his kingship is one that shall never be destroyed.

The passage centers on two prominent figures – an “Ancient of Days,” a senior figure who presumably represents God, on the one hand, and “one like a human being” (lit., “one like a son of man”), a junior figure who is to be the ruler of the new age, on the other. As verse 9 indicates, more than one throne is prepared in heaven (“thrones were set in place”). The ontological identity of the second figure, the “son-of-man-like” individual, remains obscure (is it divine or human?). The passage is often discussed in scholarship in relation to prebiblical mythological sources, where a young deity rides on the storm clouds and takes an active role next to an aged deity. However, it is not clear how relevant such literary archeology is for understanding the contextual meaning of this passage (cf. Emerton 1958; Collins 1993: 280–294).

Another biblical passage that is frequently referenced in discussions on binitarian thought is Proverbs 8. Here, wisdom is depicted as a woman of divine status, abiding with God before the creation of the world:

²⁹ When the sea was assigned its limits,

So that its waters never transgress God’s command;

When the foundations of the earth were fixed,

³⁰ I was with God as a confidant (or: protégée),

A source of delight every day,

Rejoicing before God at all times …

This portrayal of Lady Wisdom is also found elsewhere in Proverbs (e.g., 1:20–33), where she extends guidance to humanity, effectively acting as an intermediary between God and humans. Nonetheless, Wisdom’s precise relationship to God – namely, whether she is a child born of (or created by) God before the creation of the world, or rather, she is a preexistent entity aligned with God – remains a subject of scholarly dispute.

The impact of these passages on postbiblical Jewish thought is profound and widespread. Three examples suffice to illustrate this point:

1. (1) The First Book of Enoch (Feldman et al. 2013: 1359–1452), mostly composed by the early second-century bce, portrays the antediluvian character of Enoch ascending alive to heaven and undergoing a spiritual transformation. He becomes the chief of the archangels, the immediate attendant on the Throne of God (referred to as “the Head of Days”; cf. the “Ancient of Days” in Daniel), or the godlike “Son of Man.” However, the extent of Enoch’s transformative elevation – whether into an angel, or more radically, into a divinity – remains unclear.

2. (2) The Wisdom of Solomon (Feldman et al. 2013: 1903–1923), a Hellenistic work written somewhere between 100 bce and 50 ce, offers an exhortatory discourse and elaborates on the nature of divine Sophia or Lady Wisdom. The author, identifying himself as King Solomon, the biblical epitome of wisdom, expresses his fervor for Sophia in a prayer, referring to her as God’s throne partner: “O God of my ancestors and Lord of mercy … give me the wisdom that sits by your throne … ” (9:1–4). The text intertwines the primordial notion of wisdom in Proverbs 8 with Solomon’s famous prayer in 1 Kings 3:6–9. In so doing, it portrays Wisdom as an intermediary or hypostasis that empowers humans to govern the universe in “holiness and uprightness.”

3. (3) The Dead Sea Scrolls also present instances of similar patterns. In the fragmentary text known as the Self-Glorification Hymn (Feldman et al. 2013: 1924–1926), an anonymous figure describes himself as seated in heaven with the company of the celestial beings. Here is part of the hymn:

Wh[o …] has been rejected [by humans] like me?

[And who] compares to [me in enduring] evil?

[No teaching] compares to my teaching.

[For] I sit [… in heaven]

Who is like me among the divine beings (or angels)? …

The final line poses a rhetorical question, alluding to Exodus 15:11, where the question concerns YHWH: “Who is like you, O YHWH, among the god/divine beings?” The speaker, therefore, not only compares himself to angels but also with YHWH. In so doing, he presents himself as the suffering servant of God in Isaiah 53, thus aligning himself with the image of the suffering Messiah. Various interpretations have been proposed regarding the identity of the speaker. Some suggest the speaker could be the archangel Michael, while others argue he may be the eschatological high priest who would instruct righteousness at the end of days. Alternatively, some believe the speaker could be an actual leader of the Qumran community who saw himself as the Messiah and was regarded as such by his followers.

These instances clearly demonstrate that Christological concepts in the New Testament – such as portrayal of Jesus not only as the eschatological “Son of Man” (Mark 14:62; Acts 7:56; Rev 14:14) or the primordial “Logos” (John 1:1), but also as a second or junior “God” (John 1:18; 20:28; 1 John 5:20) – were not entirely new inventions. Instead, they were deeply rooted in the theological categories well established in pre-Christian Judaism.

Binitarian Thought in Rabbinic Judaism

It is commonly asserted that rabbinic Judaism wholly rejected binitarianism. However, the issue is more nuanced than generally assumed (Boyarin 2001: 89–147; Schäfer 2020).

In truth, rabbinic literature consistently endeavors to prevent any interpretation of scripture that might suggest a plurality of divine person. Consider, for example, the Daniel text mentioned earlier. Rabbinic sages subjected this passage to thorough examination for several reasons. Firstly, its portrayal of God as an elder with white hair contradicts other depictions of God as a warrior (Exod 15:3) or as a youth with black hair (e.g., Song 5:11). Secondly, the passage itself could be construed as implying the existence of two thrones in heaven: one for the senior deity and the other for the junior partner (BT Hagigah 14a; for different variations of this discussion in rabbinic sources, see Schäfer 2020: 71–98).

The first conundrum is resolved by the idea that God changes the appearance in the way best fitting the context. As stated: “In court session [in Daniel 7], none is more fitting than an elderly appearance; in war [in Exod 15], none is more fitting than a young appearance” (BT Hagigah 14a).

Regarding the second conundrum, the Rabbis proposed several solutions (BT Hagigah 14a). One suggestion is that one throne is for God and the other is for the Messiah-King David (thus, heaven by no means contains two Gods). Another proposal is that the two thrones are for two attributes of the one God – namely, justice and mercy (thus, there is no implication of two thrones for two divine persons). Alternatively, what appears to be a second throne could be interpreted as a footstool – that the verse portrays just one set of chair and ottoman, so to speak (thus, there is no hint of dualism even within God).

Furthermore, this consideration of the Daniel text is followed by an account of Elisha ben Avuyah, who misunderstood a vision he had in heaven (BT Hagigah 15a; see Schäfer 2020: 113–119). The vision features an archangel, called Metatron (possibly signifying “one on the throne beside”), seated in heaven to record the virtues of Israel. Elisha mistakenly concluded that there are “two powers” in heaven – God and Metatron. For this and for other reasons, Elisha became the arch heretic of rabbinic Judaism, also known as ’aḥer, meaning an “other” (for further insights, see Bar-On and Matanky: 2020).

It is true, therefore, that the rabbinic sages considered the binitarian idea of two Gods heretical and sought to eradicate it. Nonetheless, binitarianism persisted in rabbinic theology through a subtle avenue – the category of the Torah.

Recall the text-centeredness of rabbinic Judaism, with Torah study seen as the paramount religious duty. The sags elevated scripture to such a degree that it seems, at times, to have taken much of God’s place in Jewish consciousness. Moreover, they often personified the Torah as a living entity, an embodiment of divine life or living word. This emphasis on the Torah introduced a certain degree of internal tension or duality within rabbinic theological framework, reminiscent of the metaphysical category of Jesus as Logos in Christianity. For example, consider the following rabbinic statement asserting the primordial status of the Torah: “… [Long] before the world was created, the Torah was written and placed on the bosom of the Holy Blessed One” (Avot of Rabbi Nathan 31:3). Anyone familiar with the prologue to the gospel of John (“No one has ever seen God … [except for] the only Son, who is in the bosom of the Father …”) cannot miss the typological resemblances between the two texts (Boyarin 2001: 283).

In this regard, the Torah and Jesus Christ can be seen as functional equivalents: just as Jesus is central to Christians’ faith, the Torah holds paramount importance for the Rabbis. For the sages, knowledge of God is inseparable from the Torah, much like how Christians view divinity through Christ. While Torah-centered religiosity might appear to outsiders as compromising belief in God’s oneness, this is not the case for the rabbinic sages. Just as God and Jesus Christ are inseparable for Christians, God and the Torah are two-in-one for the sages.

As Yochanan Muffs has pointed out to me, the binitarian notion of the Torah in rabbinic thought can be traced back to a later phase of biblical religion, notably in Psalm 119. Here, God and Torah are interchangeable, and expressions typically reserved for the worshiper’s relationship to God are applied to the Torah and divine commandments. For instance: “I lift up my hands to Your commandments” (v 48; lifting hands being a gesture of prayer; cf. Ps 63:5). Other examples include: “I cling to Your decrees …” (v 31; cf. Deut 13:5); “… I have turned to Your precepts… .” (v 45; cf. Amos 5:4); “… I love Your instruction (or: Torah)” (v 113; cf. Deut 6:5). Here, we have an instance of Torah piety, foreshadowing the text-centeredness of rabbinic Judaism (Fishbane 1989: 66; Halbertal 1997: 8).

During the medieval period, particularly among the Kabbalists, binitarian concepts of Torah evolved into a complex theological notion, wherein the Torah itself is identified as divinity. Moses Maimonides, the eminent medieval Jewish philosopher, appears to also entertain a binitarian notion of the Torah, albeit perhaps only in the poetic sense. For instance, he draws from Jeremiah 1:5, replacing God with the Torah in the following statement: “I, Moses, declare … that before I was created in the womb, the Torah knew me; and before I was born, it consecrated me to its study” (from his Letter to the Sages of Lunel).

Political Idolatry and Legitimacy of Non-Jewish Authority

Living under gentile rule, whether in their native land or in the Diaspora, forced the sages to grapple with the dilemma of political idolatry: How much could they recognize the legitimacy of non-Jewish authority without compromising their loyalty to their true sovereign, the one God?

This issue, too, elicited diverse responses. On one side of the spectrum were the Jewish zealots who adamantly opposed foreign rule. For them, even mundane civic duties such as paying taxes to the emperor amounted to worshipping a foreign deity, thereby undermining their exclusive allegiance to YHWH. A notable example is found in Josephus’ account of the Roman siege of the Masada fortress around 73 ce. In that account, the rebel leader Eleazar Ben-Yair delivered a defiant speech to his followers, who ultimately chose mass suicide over surrendering to the Romans:

Brave and loyal followers! Long ago we resolved to serve neither the Romans nor anyone other than God … . The time has now come that bids us to prove our determination by our deeds. At such a time, we must not disgrace ourselves… . I believe it is God who has granted us this privilege, that we can die nobly and as free individuals … .

Note well: according to this portrayal, the zealot leader not only “resolved to serve neither the Romans nor anyone other than God” but also believed that the fall of Masada was not the result of the might of the Roman arms. Instead, it was seen as a manifestation of divine providence – a God-given “privilege” for the resistance fighters to demonstrate their sublime nobility and inner liberty (Cohen 1982; Boyarin 1997).

On the other side of the spectrum were those who took a prudential approach. They saw it necessary to fulfill their civic duties to the non-Jewish authorities of their time. They recognized the reality of foreign rule and were willing to coexist in a society with pagan practices and symbols, as long as they could maintain their religious practices privately and shield themselves from idolatry (Urbach 1999; Furstenberg 2010). For them, a divine command in Jeremiah urging the Babylonian exiles to “seek the welfare of the city to which I have exiled you and pray to YHWH on its behalf; for through its welfare, you shall have your welfare” (29:7) served as both a biblical precedent and a prudential rationale for accepting foreign rule, whether within or outside the land of Israel. Relatedly, these sages also developed a legal principle called dina de-malkhuta dina (the law of the sovereignty is the law), which meant that Jews must obey the laws of the country they reside in, unless those laws directly contradict fundamentals of Jewish norms, such as robbery, violence, or issues of personal status (BT Nedarim 28a; Gittin 10b). This principle was initially set forth by the Babylonian sage Samuel (died c. 257 ce), addressing his fellow Jews living under Sassanid rule (Elon 1994: vol. 1, 64–74; Walzer et al. 2000: vol. 1, 431–62).

Another important consideration revolves around the situation of “resident aliens” (ger toshav) who live within Jewish communities. Of particular relevance here is the rabbinic concept akin to universal natural law, known as the “Seven Commandments of the Noahide Laws.” According to the sages, these laws, or categories of laws, originate from the early chapters of Genesis and encompass prohibitions against (1) blasphemy, (2) idolatry, (3) sexual perversion, (4) murder, (5) robbery, and (6) eating flesh from a living animal, as well as (7) the injunction to establish a legal system (BT Sanhedrin 56a; cf. Hullin 92a). These laws are considered fundamental for civilized human life and are believed to have been given to all of Noah’s descendants, meaning humanity in general. Consequently, they are binding on both Jews and non-Jews alike. In principle, therefore, Jewish communities can welcome foreigners who wish to maintain their own heritage and culture, as long as they adhere to these fundamental precepts (Macy 1987; Elon 1994 vol., 67–68 and vol. 4, 1854–1856; Walzer et al. 2000: vol. 2, 445–471). Some later authorities add that gentiles must not only uphold the Noachide Laws but also recognize their divine origin (e.g., Maimonides, MT, Kings and Wars, 8:11).

Limits of the Prudential Attitude: Not to Desecrate the Name

As mentioned earlier, the prudential attitude of accommodation in rabbinic Judaism had its own limits. There was a particular emphasis on avoiding ḥillul ha-shem (“the desecration of the [divine] Name”; cf. Lev 22:32), which refers to actions that would tarnish Judaism in the eyes of non-Jews. This concept arises from the belief that the honor of God is closely linked to the Jewish people, so any dishonorable conduct by a Jew brings disgrace not only on individual but also on the entire Jewish community and on God. Therefore, individuals who are seen as representatives of the Jewish community must be especially careful to maintain impeccable behavior in public (BT Yoma 86a). Conversely, the opposite concept is qiddush ha-shem (“the sanctification of the [divine] Name”), which in colloquial terms often refers to martyrdom for Jewish belief. Sacrificing one’s life for God is considered the ultimate act of sanctifying the divine Name.

Among the rabbinic archetypes of qiddush ha-shem is the martyrdom of Rabbi Akiva. During the Hadrianic persecutions (c. 135–138 ce), many sages faced martyrdom at the hands of the Romans. According to tradition, Akiva, too, met his death by being flayed alive for defying the Roman decree banning Torah study (BT Berakhot 61b). Even during his ordeal, when the time came to recite the Shema, Akiva is said to have prioritized that obligation (JT Sotah 5.7, 20c; Berakhot 9.5, 13b). In doing so, he not only reaffirmed his unwavering devotion to the one true God with undivided love and serene determination but also, implicitly, rejected the deification of the emperor and pagan authority (Lieberman 1974; Fishbane 1994: 69). Following Akiva’s legendary example, the tradition of reciting the Shema before martyrdom has persisted throughout the ages (Boyarin 1999, 2014; Holtz 2017).

Philo of Alexandria: An Antecedent to Medieval Jewish Philosophy

A comment is in order on one of the most notable figures in Hellenistic Judaism – Philo of Alexandria (c. 20 bce–50 ce). Born into a prominent Jewish family in Alexandria, Egypt, Philo embodies a unique blend of Jewish faith and Greek philosophy. His works not only display a deep understanding of Greco-Roman education but also exhibit a steadfast dedication to the Jewish laws and traditions (Schwartz 2009; Runia 2013).

Unlike the sages of rabbinic Judaism, Philo regards the reality of God as incorporeal, non-composite, and essentially beyond human understanding. He therefore comprehends divine oneness in terms of radical otherness and ultimate simplicity. According to his perspective, God is the singular supreme principle upon which the existence of all beings depends. From this viewpoint, polytheism is seen as a metaphysical misconception arising from the failure to acknowledge the fundamental distinction between this primary principle and all other aspects of existence (Radice 2009).

Philo adopts the concept of Logos as a means to bridge the gap between divine transcendence and the divine working experienced in the physical world. He thereby sought, in part, to address a common perception among the Hellenistic people of his time, who often viewed the Jewish belief in an invisible God as a brand of atheism. Philo’s Logos, which is both connected to and distinct from God, combines elements of biblical Wisdom and the Platonic Logos. Notably, Philo goes as far as to refer to it as a “second God” (Questions and Answers on Genesis 2:62). Here, too, we have a form of binitarianism – God and Logos as two-in-one (Boyarin 2001: 249–252; Boyarin 2004: 112–127; Schäfer 2020: 62–64).

Philo employed allegorical interpretation to unveil the hidden meanings within the Jewish Scriptures, which he deemed compatible with Greek philosophy. Although some early and medieval Christian thinkers embraced some of Philo’s ideas and allegorical methods (and some even considered him as a Christian theologian), his influence on rabbinic Judaism and medieval Jewish philosophy was minimal. Nevertheless, his synthesis of Jewish thought and Greek wisdom foreshadowed the theological efforts of the medieval period, whether within Jewish, Christian, or Islamic contexts, to demonstrate the essential compatibility between scriptural faith and critical inquiry (Winston 1985; Termini 2009).

Medieval Phase

The medieval period witnessed a new flourishing of Jewish thought, spurred by encounters with intellectual and spiritual traditions in Christianity and Islam, as well as with Greek philosophy, mediated by those traditions. Consequently, fundamental categories of Judaism, previously accepted as revealed ideas, underwent thorough reexamination.

While a diverse variety of thinkers emerged during this period, many can be categorized into one of two major traditions in Jewish thought: philosophical or kabbalistic. The two traditions, each exhibiting a wide range of internal variations and competing trends, differed substantially in orientation, concern, and style. Specifically, philosophical trends relied on rational thinking and often embraced the concept of divine simplicity to explain the reality of divinity and its oneness, whereas their kabbalistic counterparts employed mythopoetic and theurgic thinking, maintaining the notion of divine complexity.

These two traditions, however, shared two crucial features. First, both revisited the premedieval understanding of God as a relational subject and reinterpreted it, in one way or another, through causal categories. Secondly, both maintained that their distinct understanding of divinity and its oneness is encrypted in scripture as part of its hidden and deeper meaning, which can be uncovered only through esoteric interpretation (Shatz 2003; Halbertal 2007).

Nonetheless, the relational understanding of God as a personality has not completely vanished from the medieval phase. As we shall see, there are those who retain and refine such understanding of the divinity.

Background of Philosophical Trends

During the medieval period, both Christians and Muslims actively worked to systematize their theological doctrines and recast them in the language of philosophy. This effort was motivated not only by exposure to diverse theological perspectives within and beyond their respective traditions but also by their encounter with the Greek philosophical tradition. While Christian theologians had engaged with Greek philosophy long before the emergence of Islam, Muslim thinkers started grappling with it in the eighth and ninth centuries, prompted by the translation of many Greek writings into Arabic for the first time (Kraemer 2003; Tirosh-Samuelson 2003; Schwartz 2005: 1–26).

In the Jewish tradition, exposure to cross-religious interactions and to Greek philosophy gave rise to philosophical trends characterized by a distinct set of attitudes:

Rationalism: a stance that elevates human reason as an arbiter of truth. It draws attention to a tension between two sources of truth and knowledge – faith and reason. This tension must be addressed, if not resolved, with rationally based argumentation. Consequently, the validity of religious claims needs to be reconsidered in terms of rational truth.

Causal thinking: a tendency to explain all existence in causal terms. This tendency, in turn, promoted abstract and impersonal (demythologized) concepts of reality, while shifting the understanding of divine reality from interpersonality to causality. Efforts were made to purify the concepts of divinity from any features of folk religion, such as imagination, superstition, and anthropomorphism.

Doctrinal (or scholastic) faith: an attempt to develop a proper metaphysical conception of God and articulate it, to the extent possible, through dogmatic principles and abstract propositions. Acceptance of such principles became a prerequisite for membership in the religious community and the promise of a place in the world to come. Connectedly, the opening verse of the Shema (Deut 6:4) was often interpreted as a doctrinal statement about God’s essence, with relational interpretations marginalized in philosophical discourse.

Esotericism: Recognizing scripture as the source of divine truth and religious knowledge, biblical texts were seen as expressing abstract ideas and theological concepts in non-philosophical terms. Therefore, exegetical skill was deemed essential for uncovering the rational intent beneath the literary veil of the texts.

During the medieval period, the study of philosophy and nature was not necessarily seen as a threat to faith; rather, it was often viewed as a means to deepen and fortify it. This perspective arose from the belief that both reason and nature were of divine origin, reflecting the greatness and wisdom of the divine. Some thinkers went as far as to argue that philosophy and science are not only complementary to faith but also indispensable for achieving the highest levels of religious devotion, rooted in genuine love and awe of God. As Maimonides stated: “The love is proportionate to the knowledge” (MT, Repentance, 10:6; Twersky 1972: 24). In this view, philosophy and science served a redemptive purpose. Consequently, the relationship between faith and reason was conceived differently from the prevailing modern perspective, which often portrays it as a conflict between two opposing forces.

The influence of philosophical reasoning generated a tendency in Jewish thought to reverse the theological premise: instead of considering God as perfect and ultimate in its own terms, whatever philosophy and science defined as perfect and ultimate was now believed to be God. Therefore, whenever the philosophical and scientific understanding of nature, especially the ultimate ground of being, evolved, traditional concepts of God underwent corresponding readjustments. Natural reason was thus presumed to hold sway over theology, unless its limitations were recognized. This principle also extended to scriptural hermeneutics, as Jewish philosophers continuously revisited traditional interpretations in light of evolving human thought. As Maimonides noted: “the gates of scriptural interpretation are never closed” (Guide 2:25).

The Greek Legacy

The Greek philosophical tradition, to which the Jewish thinkers of the Middle Ages were exposed, was diverse rather than monolithic. It encompassed various intellectual traditions that offered different models for conceptualizing divine reality.

One prominent model was the Aristotelian conception of God as the Unmoved Mover – the primary cause sustaining the existence and operation of the cosmos. This conception stems from the idea of perfection as unaffected, unchanged, and self-sufficient, qualities attributed to God. According to this view, the notion of God desiring something or loving someone is logically impossible, as perfection neither lacks nor desires anything. Furthermore, the notion of God as the Unmoved Mover implies divine immateriality and non-compositeness, as anything material or composite is subject to change and therefore impermanent, and also incapable of sustaining cosmic existence.

Another highly influential model was the Neoplatonic conception of God as transcending being, surpassing any conceptualization, categorization, and articulation – thus, essentially unknowable and indescribable. In this framework, negative (apophatic) statements are considered more suitable for expressing divine truth (e.g., it is not accurate to say that God exists in the usual sense; rather, all we can say is that God is not nonexistent). This tradition views the world as emerging through a process of emanation from God, with every being arising from the potency, or life force, which overflows from God through a gradation of existence.

The impact of these and other Greek traditions extended not only to medieval philosophers, both Jewish and non-Jewish, but also to mystics of each Abrahamic tradition. As they absorbed these cultural influences, Jewish tradition engaged in a wide range of systematic inquiries into theological subjects.

Saadya: The Father of Medieval Jewish Philosophy

The first major medieval Jewish philosopher is Saadya Gaon (882–942). Saadya spent his entire life under the aegis of Islamic civilization, first in Egypt and then in Babylonia. He developed a unique synthesis of Jewish tradition with Greco-Arabic philosophy. One of his monumental works is The Book of Beliefs and Opinions, a polemical treatise that reflects Platonic and Aristotelian influences. This work articulates a conviction shared by many medieval philosophers: that natural reason and revealed religion, while distinct, are essentially compatible (Stroumsa 2003; Brody 2013).

According to Saadya, philosophy and revelation can lead to the same conclusions, and yet, we need both. For, on the one hand, philosophy not only deepens our understanding of the religious truths passed on by tradition or verifies their credibility, but also equips to address arguments from polemical opponents. On the other hand, revelation – or “reliable tradition” based on divine revelation – is equally necessary, because not all individuals possess the capacity for rational inquiry, and some may require guidance for their inquiry to be effective. At the same time, Saadya contends that certain realms of knowledge, such as Jewish dietary laws, can only be accessed through revelation. The same holds true for the true nature of God’s essence. While Saadya acknowledges that we can apprehend aspects of God through divine action and relationships with the world, God’s essence remains ultimately unknowable to humans. Consequently, Saadya concedes that describing God as “creator” merely signifies the existence of creation. Nonetheless – and this is striking – Saadya takes little issue with describing God in positive terms (Lobel 2007: 10–13, 102–116).

Saadya understands the divine reality and its oneness in terms of incorporeality and indivisibility. He argues that since God is the cause of all corporeal existence, God must be incorporeal, transcending corporeal attributes of quality or number, and therefore must be singular. While Saadya acknowledges that the analysis of God as creator reveals three essential attributes – life, power, and knowledge – he does not interpret this as implying plurality within God. Instead, he sees these three attributes as logically indivisible aspects of the Creator, united in God’s divinity. It is solely due to the limitations of human language that we find ourselves using three different words to describe God (Lobel 2007: 103–104).

Saadya thus rejects the notion of God as concrete actuality with a supernal body or visage, and yet, he seems to support the notion of divine agency and will (as implied by the idea of Creator, which entails volition, the will to create). In this regard, Saadya’s conception of God falls short of Maimonides’ Unmoved Mover. For, as we shall see shortly, Maimonides’ God is both immaterial and impersonal, whereas Saadya’s God is immaterial but not entirely impersonal – his God retains a sense of agency, possessing a degree of self or subjectivity.

Baḥya: A Jewish-Sufi Thinker

Baḥya Ibn Paquda (c. 1050–1120) was a synthetic thinker who resided in Muslim Spain. He produced a creative integration of rabbinic Judaism, rationalist philosophy, and the tradition of Islamic mysticism known as Sufism. Unlike Saadya’s scholastic and polemical approach to theology, Baḥya’s method of exploration was holistic and devotional (Sviri 1996; Fenton 2003; Lobel 2007).

According to Baḥya, the ultimate aim of human life is to achieve the highest stage of love for God – devoting oneself solely to God and serving God for who God truly is. Baḥya perceives God as the transcendent source of all existence, hidden and physically unlocatable, yet present throughout the entire world. Hence, Baḥya quotes an anonymous Arabic verse, presumably of Sufi origin:

My God, where can I find You—

no, rather where can I not find You?

You are veiled and cannot be seen—

and yet, the whole world is full of You!

Duties 1:10

In Baḥya’s outlook, as individuals develop an awareness that all created existence, including themselves, is an object of God’s loving attention, a new consciousness begins to emerge: a distinct sense of dependence and companionship, a real presence of the living God who loves and sustains all existence. This awareness of God’s graciousness – and more importantly, of God’s true nature – inspires individuals to respond with total devotion. This devotion entails achieving unity of focus and selfhood, dedicating all actions purely to the service of this living God.

As for God’s oneness in the Shema (Deut 6:4), Baḥya views it through the lens of ontological uniqueness. God is understood as the True One, the ultimate Source that creates, sustains, and unites the diversity of this world. Since God transcends everything – including any conception of “oneness” within the world – God’s oneness surpasses all other notions of oneness. Baḥya identifies this oneness, along with eternity and existence, as among the three essential attributes of God. At the same time, he asserts, like Saadya, that these three attributes are merely nominal distinctions, all pointing to the unified essence of God. Unlike Saadya, however, Baḥya takes a Neoplatonic approach, suggesting that we can only speak about God’s essence through negation. Thus, the three attributes are essentially negative in meaning. Accordingly, the term “one” in the Shema should be understood in a negative or metaphorical sense (Lobel 2007: esp. 66–95).

Baḥya takes an even more radical stance. He adopts a Sufi perspective, asserting that God can only be truly known through the divine presence or the traces of the divine in creation, rather than through an intellectual conception of God’s essence. In other words, anything conceived in our minds or imaginations – including any notions of God – falls short of the reality of God. Therefore, we must strip away all such conceptions entirely to recognize and encounter the true, singular God. It follows that one must safeguard the mind from misconceptions of the divine to avoid idolatry, which, in Baḥya’s view, extends to mental images and misconceptions. He argues that every conception and expression is fundamentally limited and potentially misleading when describing God. As a result, Baḥya advocates for silence as the most appropriate attitude toward God. Hence, he draws on a rabbinic reading of Psalms: “‘For You, silence is praise’ (Ps 65:2) … This is like a priceless jewel [whose beauty and splendor transcend words]: the more you praise it, the more you deprecate it’” (Duties 1:10; cf. JT Berakhot 9:1, 12d; BT Megillah 18a).

Maimonides: The Foremost Jewish Scholar of All Time

Moses Maimonides (1138–1204), widely regarded as the greatest Jewish philosopher and legal scholar of all time, sought to reconcile philosophy with Jewish tradition. In this pursuit, he redefined traditional concepts of God in light of Aristotelian categories. His major works include the Mishneh Torah (“Reiteration of the Torah” or “Second Torah”), a comprehensive codification of Jewish law, and the Guide of the Perplexed, an exhaustive treatment of Jewish thought and practice. He identified the primary theological challenge as the misconceived notion of God held by worshippers, particularly the anthropomorphic view which he considered the epitome of idolatry. That is, in his view, a flawed understanding of God was more problematic than the worship of physical idols because it internalized the error, making correction more difficult. Maimonides aimed to dispel these misconceptions through the application of reason (Kraemer 2005; Halbertal 2014; Goodman 2015).

Maimonides conceptualized the reality of God and its perfection through three categories: ontological primacy, radical oneness, and absolute incorporeality.

Ontological Primacy: God is the ultimate cause of all existence. Perfect in every respect, God is self-sufficient, eternal, and ontologically different from and transcendent to any other existence. According to Maimonides, God is not a relational subject and has no active or volitional role in creation; rather, the world exists by the virtue of God’s very existence. Note also that if God lacks volition and initiation, revelation cannot be understood as divine speech to humanity but rather as a naturalistic process, such as human discovery of religious truth or the intellectual pursuit of perfection.

Radical Oneness: God is one in the sense of both incomparability and absolute unity. God’s oneness is one of its kind because there is nothing in the world that shares any similarity with God, and God’s essence is unified to the extent that it transcends any internal divisions. Consequently, it is impossible for God to be anything other than one. According to Maimonides, understanding this unique oneness is what is commanded in the opening verse of the Shema (Deut 6:4).

Absolute Incorporeality: God, being perfect and infinite, cannot be material, as all material things are finite and perishable. Furthermore, God’s incorporeality is essential for God’s omnipresence, as a physical body would limit God’s presence to a single location. For Maimonides, as in Aristotelian philosophy, corporeality is a prerequisite for plurality and compositeness, while incorporeality is a sufficient condition of oneness; hence, God’s incorporeality, too, points to God’s oneness.

These three concepts also correspond to the first three of Maimonides’ thirteen principles of faith, which he considers foundational to Judaism. Maimonides stipulates that adherence to these principles is essential for membership in the Jewish community (Shapiro 2004; Kellner 2006a).

Religious Language and Negative Theology

Anyone who accepts Maimonides’ theological outlook recognizes the inherent limitations of human language, that we cannot describe God by any positive attributes. Any attempt to ascribe such attributes to God poses a challenge to the dual aspects of divine oneness – its indivisibility and incomparability. Firstly, the basic structure of any sentence, comprising a duality of subject and predicate, fails to encapsulate God’s radical oneness, which transcends any internal divisions. Furthermore, ascribing multiple attributes to God implies internal multiplicity in God as if containing a variety of aspects, and in this regard, too, undermines God’s internal indivisibility. Secondly, language is intended to describe worldly experiences, making it inadequate for describing God, who exists beyond the confines of this world. Describing God with familiar predicates such as “mighty” or “merciful” risks diminishing God’s incomparability by likening God to worldly entities. In the end, if we truly understand God’s oneness, we realize that we cannot call God “one,” because God’s absolute unity transcends the limits of linguistic representation, and, equally important, because God’s oneness is different from any worldly experience of oneness (cf. Guide 1:58).

Thus, for Maimonides, language is inherently limited and potentially misleading when used to describe God. However, he argues that religious language can still serve three purposes in relation to God: (1) delineating God’s essence via negative (since our understanding of God’s essence is limited to what God is not); (2) describing God’s actions in the world (the only positive knowledge we have about God); and (3) evoking the Tetragrammaton, YHWH, which is not an attribute or adjective, but rather the proper name of God (for Maimonides, it signifies divine essence as “necessary existent,” existing by its very essence without external cause). Maimonides also asserts, following Baḥya, that those who truly grasp the limitations of religious language would find silence the most appropriate praise for God (Guide 1:59).

For those acquainted with the Bible, Maimonides’ theological stance may seem perplexing. If, as Maimonides asserts, God is neither corporeal nor a force within a body, why does the biblical canon depict God in corporeal terms, appearing to endorse a fundamental error? Maimonides elucidates this as a form of double language: The surface-literal meaning of the Bible caters to the multitude who rely on their imagination and struggle with abstract concepts of divinity, whereas its deeper-hidden meaning targets intellectually advanced individuals. The outer meaning addresses what Maimonides calls “necessary beliefs,” essential for social cohesion, whereas the inner meaning pertains to what he calls “true beliefs,” crucial for human perfection (Guide 3:28). While both meanings are vital for educating the entire community of Israel, the inner meaning may challenge the outer meaning as a more truthful articulation. In short, those informed should recognize that any biblical verses contradicting rational truth must be interpreted figuratively.

A Naturalistic Conception of Evil

If God is the ground of all being, does God also serve as the source of evil? According to Maimonides, this is not the case. He views evil as a privation – an absence of good – largely stemming from human ignorance regarding the nature and purpose of life and the world. Maimonides applies this perspective to both natural and moral evils. Essentially, the natural world, where humans encounter suffering, illness, and natural disasters, is not inherently evil. Instead, our perception of it as such arises from a narrow human perspective and misplaced expectations. Maimonides emphasizes that the “world follows its customary course” (Guide 2:29; cf. BT Avodah Zarah 54b). Put differently, natural evils, like illness, are merely the absence of a desired conditions, such as health. Conversely, moral evils, such as crimes or wars, stem from inappropriate desires that cannot or should not be fulfilled. Thus, individuals have the capacity to confront and mitigate both natural and moral evils by aligning their goals with the inherent nature of existence (Rynhold 2021; Shatz 2021).

Above all, Maimonides sees philosophy as having a redemptive function. It can liberate us from our own mental habits and other cognitive constraints, allowing for a deeper understanding and appreciation of divinity, humanity, and reality. Moreover, Maimonides believes that since intellect is a universal quality shared by all human beings, individuals from any religious background can potentially attain philosophical and demonstrative truths. Consequently, he is unhesitant in drawing from non-Jewish sources to support and clarify his own faith.

The Emergence of the Kabbalah

Alongside the philosophical trends within medieval Judaism, “Kabbalah” (lit. “tradition”), a movement of substantially different orientation, with intrinsic complexities and diverse variations, emerged mainly from northern Spain and southern France. Kabbalah is often identified as a brand of mysticism, but if mysticism signifies a quest for an unmediated encounter with the divine, kabbalah should not be limited to that category. For, while mystical aspects may at times seem predominant in kabbalistic discourse, its interests extend beyond mysticism to include theosophy (understanding the inner workings of the divine world), cosmogony and cosmology (understanding the origins and structure of the universe), and historiosophy (understanding the nature and process of messianic redemption). Kabbalists regard these disciplines as highly sensitive and not suitable for widespread dissemination due to their potential profound consequences if mishandled. All in all, kabbalah is thus best viewed as a distinct form of esotericism (Scholem 1961, 1987; Idel 1988; Hallamish 1999).

Historians commonly attribute the majority of kabbalistic teachings and practices to the medieval era. Key texts in this tradition include Sefer ha-Bahir (the Book of Illumination) and Sefer ha-Zohar (the Book of Splendor), which compile various kabbalistic teachings. While Sefer ha-Bahir is traditionally attributed to the second-century rabbi Naḥunya ben ha-Qanah, scholars generally believe it was compiled by an unknown author in twelfth-century northern Spain of Provence. Sefer ha-Zohar, traditionally associated with a group of second-century rabbis led by Shimon bar Yoḥai, is believed by scholars to have been primarily written in the late thirteenth century, notably by Moses de Leon (c. 1240–1305) and other kabbalists in northern Spain, specifically Castile. Over time, the Zohar has attained a canonical status akin to that of the Bible and the Talmud within the kabbalistic tradition. These three compilations are often considered by kabbalists as the fundamental texts of Jewish spirituality (Tishby 1989; Green 2003).

Multiplicity and Unity within Divinity

Like Maimonides, kabbalists assert that the essence of divinity surpasses human comprehension. Unlike Maimonides, however, many kabbalists perceive the divine reality in terms of multiplicity rather than of simplicity, and this multiplicity in two distinct ways. Firstly, they understand the category of divinity as comprising two facets: hidden and revealed. The hidden aspect, known as Ein-Sof (“unending” or “the infinite”), remains entirely concealed and inaccessible to humans. This primary facet reveals itself through a complex and dynamic structure of sefirot (often ten in total), which are described as “emanations” or “aspects.” Secondly, within the revealed aspect of divinity, each sefirah represents a unique realm of the divine world, characterized by distinct attributes, and many of them have a specific gender, male or female. Consequently, the premedieval notion of divine personhood undergoes radical fragmentation, making the entire system of sefirot resemble a pantheon. Be that as it may, the ontological relationship between the sefirot and Ein-Sof remains somewhat ambiguous. While some kabbalists view the sefirot as integral components of Ein-Sof, others regard them as instruments or vessels through which Ein-Sof interacts with the world. Overall, the divine reality is conceived in organic terms, akin to a living ecosystem, where the concept of interpersonality is internalized within the divinity through its male and female aspects (Idel 2005; Afterman 2020).

An important aspect of this revealed dimension is the female nature of the tenth sefirah, the Shekhinah (lit. “residence” or “presence”). While the term shekhinah in rabbinic literature simply denotes God’s presence without any implication of gender, in kabbalistic writings, it takes on a distinct meaning. This feminine aspect is often depicted as being separated from the integrated divine structure and existing in a state of exile within the world. Kabbalists see it as their responsibility to reunite this foundational aspect with the masculine aspect of divinity through the performance of rituals and religious precepts. Correspondingly, they perceive transgressions and sinful behaviors as causing a division or rupture within the divine, separating its male and female aspects (Green 2002; Wolfson 2006: 17–185; Tirosh-Samuelson 2011).

In Kabbalah, therefore, the existence of evil is explained, in part, as a manifestation of imbalance within the divine realm or, more generally, within the world at large. Kabbalists also describe a realm of unholy or demonic forces that structurally parallels the holy realm of sefirot, often referred to as Siṭra Aḥra (the “Other Side”). Various interpretations exist regarding the relationship between the two realms, which can generally be categorized into dualistic or monistic approaches. The dualistic approach perceives the two realms as intrinsically antithetical, hence, the goal is to obliterate evil through ritual practices. In contrast, the monistic approach regards the demonic as either an aspect of the divine or a derivative thereof, hence, the goal is to reintegrate evil into the good through rituals, thereby restoring the unity of the divine that would signify the ultimate redemption (Dan and Kiener 1986: 165–182; Hallamish 1999: 167–182).

In general, kabbalists tend to conceive of divine oneness in a potential rather than actual sense, placing significant emphasis on human involvement in its realization. This tendency becomes particularly evident in later developments of Kabbalah, such as Lurianic Kabbalah, which is based on the teachings of Isaac Luria (1534–1572). Practitioners of Lurianic Kabbalah see the actualization of divine union, or what they often call tikkun olam (“repairing the world”), as the ultimate purpose of their theurgic activity and religious life in general (Fine 2003). This commitment is also reflected in a brief kabbalistic formula, l’shem yiḥud (“For the sake of the unification”), which may be uttered before preforming a commandment to restore the primordial unity of the divine. For kabbalists, furthermore, the recitation of the Shema, particularly the opening line, “Listen, O Israel! YHWH our God, YHWH is one” (Deut 6:4), serves a theurgic purpose – to reunite the masculine and feminine aspects of divinity and anticipate the messianic redemption. Interestingly, these and other rites related to divine romance have spread rapidly among Jewish communities worldwide, although their esoteric implications remain generally unconsidered. The liturgy of the Friday night service, especially the poem Lekha Dodi (lit. “Come my beloved”), is infused with aspirations for this reunion and consummation (Hallamisch 1987; Kimelman 2002; Wolfson 2004: 296–332, 367–371).

The Doctrine of Sefirot as Internal Polytheism?

To those unfamiliar with it, the doctrine of sefirot may appear as a form of internal polytheism, seemingly contradicting God’s absolute unity. Indeed, objections to the notion of sefirot have arisen even among some kabbalists. Abraham Abulafia, the founder of prophetic kabbalah in the thirteenth century, considered it heretical, equating it to, and even deeming worse than, the Christian notion of the Trinity due to its belief in ten aspects rather than three. Accordingly, these kabbalists have explored alternative methods to attain the desired quality of consciousness, such as contemplating combinations of letters.

For its followers, however, the sefirotic doctrine provides an invaluable framework for understanding the complexity and dynamic nature of divinity. This understanding resists being reduced to a set of abstract propositions, despite efforts by philosophical thinkers to do so. In this context, kabbalists resemble quantum scientists, who resort to an “emergence model” of reality rather than a reductionist one. These scientists perceive the physical world, including gravity and other forces within it, as emerging from a deeper underlying reality and, like kabbalists, acknowledging that each parallel realm operates according to a complex network of distinct factors and principles (Scholem 1974; Hallamish 1999: 121–166).

Kabbalistic Concepts of Torah

Kabbalists develop an ancient notion of the Torah as an incarnate form of divine presence. They often identify the Torah as the sefirot, as the divine name, or otherwise as the icon and body of the divinity. In the first case, the reality of God supposedly manifests itself as the Torah on different levels of existence, thus corresponding to various kinds of sefirot. In the second case, some kabbalists understand the entirety of the Torah as a sequence of divine names, emanating from divine wisdom in an esoteric sense, while other kabbalists identify all of the Torah as the Tetragrammaton (YHWH). Regarding the third case, the Torah appears, at the peak of mystical moments, as the scriptural body of God. In every instance, engagement in scriptural exegesis and observance of commandments enables the reader to encounter the divine or even to unite with and embody that reality (Hallamish 1999: 207–246; Idel 2012).

In the realm of scriptural hermeneutics, Kabbalists also acknowledge multiplicity. Like Maimonides, they posit two layers of meaning within the sacred texts: the outer and inner, with the inner reserved for advanced readers. However, their hermeneutic approach differs notably from Maimonides’ in two respects. Firstly, unlike Maimonides, who attributes a multilayered structure only to passages that appear to contradict natural reason, kabbalists view all scripture as possessing this quality. Secondly, while Maimonides presents the two layers in binary opposition and prioritizes the inner one, kabbalists tend to see the two as inherently related, considering neither layer less significant. Their understanding of scripture may stem from their belief in a multilayered reality, wherein the world of being consists of parallel realms: the supernal and the lower (Idel 2000; Wolfson 2004, 2007: 56–110).

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This much illustrates the significant differences in theological outlook between Kabbalistic trends and their philosophical counterparts. To philosophers, kabbalistic concepts of God may seem nonexistent, erroneous, and polytheistic. Conversely, to kabbalists, the God of philosophers may appear indifferent, lifeless, and sterile. However, it is important to note – as I have previously noted – that thinkers on both sides share two crucial tendencies. Firstly, they all revisit the premedieval understanding of divine personhood, either by rejecting, marginalizing, or fragmenting it, and, in varying ways, advance a causal conception of the divinity as the ultimate explanation. Secondly, they all argue that their distinct understanding of divine reality and its oneness is encoded in scripture as part of its hidden and deeper meaning, which can only be uncovered through esoteric interpretation.

The relational understanding of God as a unified persona, it must be noted, did not completely vanish during the medieval phase. In addition to the philosophical and Kabbalistic traditions, we can identify a distinct trend advocating such an understanding. To explore this, we must go back a few decades prior to Maimonides and consider the theological stance of Judah Halevi. In many respects, Halevi’s theological writing can be seen as a response to Maimonides’ theological work, even before the latter was composed.

Halevi between Philosophy and Mysticism

Judah Halevi (c. 1075–1141), a Spanish poet and religious thinker, is renowned for his Hebrew poetry and his theological masterpiece, commonly known as The Kuzari. This work, presented as a five-part dialogue primarily between a gentile king of the Khazars who converts to Judaism and the Jewish sage who instructs him, aims to demonstrate the finest aspects of Jewish religion. This text, along with Halevi’s poetic works, reflects the persona of a representative figure among the medieval Judeo-Arabic elite, possessing an exceptional command of both Jewish learning and Greco-Arabic education (Sviri 1996; Lobel 2000; Fenton 2003).

Unlike other medieval Jewish philosophers, Halevi did not seek to reconcile his religion with the prevailing philosophy of his time. Instead, his focus was on delineating the boundaries of philosophical reasoning and highlighting the uniqueness of revelatory knowledge (Kogan 2003). For Halevi, revelation lay not within but beyond the confines of philosophy. His stance can be described as rational or meta-rational (though not rationalist), as he offered a stern critique of philosophy while extensively elaborating on Jewish religion, all firmly rooted in rational arguments. Thus, long before Pascal, Halevi discussed, among other things, the essential difference between the God of Abraham and the God of the philosophers, particularly the Aristotelians.

While utterly transcendent, Halevi’s God – that is, the God of Abraham – is portrayed as personal, accessible, and intimately related to human beings. True, like the Aristotelian God, Halevi’s God lacks corporeality and stands apart from any imperfections of the material world. And yet, unlike the Aristotelian God, Halevi’s God demonstrates a profound concern for the fate of the world and has revealed to a particular group of people, Israel, a means of redemption – the divinely commanded actions. Just like Baḥya, Halevi expresses this paradoxical sense of divine presence in one of his renowned poems: “Where can I find You, Lord?—Your place is high and hidden. But where can I not find You, Lord?—Your glory fills the world!” (Scheindlin 2008: 43). He agrees with Baḥya that divine presence surpasses human comprehension. Or put differently, for Halevi, we can only grasp the divine when it reveals itself to us and guides us through revelation. Herein lie the limitations of philosophical reasoning and investigation.

When it comes to divine oneness, Halevi asserts – again, just like Baḥya – that we cannot attribute the term “one” to God in the ordinary sense because God’s oneness transcends any conception of “oneness” in the world. Following Baḥya, Halevi therefore interprets the term “one” in the Shema as negation or metaphor, thereby foreshadowing Maimonides’ elaborate stance of negative theology (Lobel 2005: 173).

Halevi and Maimonides

As many scholars have discussed, Halevi’s view diverges significantly from that of Maimonides (Wolfson 1912; Hartman 2000: 26–87; Kreisel 2001: 94–315, 595–640). Three key differences are particularly notable:

1. (1) While Maimonides’ notion of the ultimate resembles that of a divine watchmaker who sets the world in motion and remains perpetually hidden and silent, Halevi’s understanding of the ultimate is of a living God – one with whom we can be in relation.

2. (2) In Halevi’s project, the primary concern is not solely the content of revelation and its reconciliation with philosophical truths, as in Maimonides’ work. Of great significance to Halevi is the certainty of revealed knowledge acquired through direct experience and spiritual insight – what the inner eye can discern beyond the reach of human reason.

3. (3) Unlike Maimonides, Halevi asserts the Jewish singularity of prophetic capacity, suggesting that only the Jewish people possess the tradition and capacity for connection with the divine, passed down from ancient times (Lobel 2000: 35–40; Kellner 2006b: 216–264). While Halevi’s perceived ethnocentric perspective may indeed strike as objectionable from a modern egalitarian perspective, it remains debatable to what extent he considers that capacity to be inherently innate – that is, how much of it he regards as a result of nature and of nurture (and also how he understands the prophetic potential of Jewish-born descendants of converts).

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While several other medieval thinkers, such as Solomon Ibn Gabirol (c. 1021–1058), Abraham Ibn Ezra (1088–1164), and Moses Taku (1250–1290), present distinct concepts of divine oneness, much of the medieval Jewish discourse on this topic can be viewed as a dynamic interplay or synergy among the trends discussed in this section. This discourse has, in turn, led to the emergence of a diverse range of theological systems and sub-trends, contributing significantly to a distinct feature of Jewish modernity: a broad spectrum of Jewish religiosities and identities (Feldman 2003; Garb 2020).

Modern Phase

The modern Jewish era is marked by the emergence of a wide-ranging array of new religious sensitivities, driven by two major factors: the encounter with global trends of secularization, such as the impact of liberalism, naturalism, historicism, nationalism, and humanism, on the one hand, and historical changes of enormous magnitude, such as the Holocaust and the establishment of the State of Israel, on the other. One defining characteristic of the modern secular world is what might be termed a “philosophy of immanence,” an outlook that considers this empirical world as the primary or sole realm of existence (Yovel 1989). With this worldview prevailing, not only does the category of a transcendent deity become an “unnecessary hypothesis” for addressing many aspects of human life, but also any concepts of God – including the belief in God’s historical presence – that are empirically untenable or morally unjustifiable undergo significant reconfiguration or are discarded altogether. No less important, self-conscious Jews who have embraced the contemporary ethos of diversity and pluralism are compelled to reconsider whether and how their Jewish outlook can accommodate the validity of other faiths and value systems. These factors have led to a broad spectrum of Jewish approaches to the divine reality and its oneness.

In what follows, I will first elucidate how this immanent worldview has shaped the condition of Jewish modernity. Then, I will discuss two pairs of Jewish thinkers to exemplify a diverse range of approaches to this Zeitgeist and the reshaping of the category of divine oneness. As you read this section, I encourage you to consider how each of these thinkers might address the following questions: If we wish to be responsible members of the modern secular world, which generally accepts this immanent worldview as a given, are we not compelled to acknowledge that all the models of divine oneness discussed in the preceding sections, along with the reality they are purported to represent, are merely products of human imagination? In simpler terms, could it be argued that for millennia, Jews have been venerating constructs of their own creation? Alternatively, can we – both Jews and non-Jews alike – still find contemporary relevance in the Jewish discourse on divine oneness, and if so, how?

Philosophy of Immanence

The age of modernity and secularization is often characterized by the radical worldview advanced by Baruch Spinoza (1632–1677), a Dutch philosopher of Portuguese-Jewish descent. This outlook, which may be termed a “philosophy of immanence,” entails a “conviction that the natural world is all there is, and that human civilization in all its aspects – knowledge, ethics, law, political legitimacy, private and social emotions, true freedom, love of God, even salvation – is derived exclusively from this world and can be attained only within it” (Yovel 2009: 335). This conviction excludes a priori the idea of transcendence, at least, from the horizon of being and cognition. If Spinoza indeed believed in God, his deity was the totality of the immanent world. Moreover, in the absence of an external doctrinal authority serving as the supreme arbiter of truth, this conviction affirms human reason as the sole available and legitimate foundation for epistemology and normativity (Nadler 2011).

This immanent revolution has exerted a profound influence on major trends in modern thought. It has manifested in diverse forms and competing models, whether they be deistic, atheistic, or agnostic, and has directly or indirectly impacted prominent thinkers of the Western world, including Kant, Goethe, Hegel, Heine, Feuerbach, Marx, Nietzsche, Darwin, Bergson, Einstein, Sartre, and many others. In other words, to exist within the climate of Western modernity entails adapting to this intellectual trajectory (Yovel 1989, vol. 2).

Spinoza sought to dissociate himself from his Jewish identity and assert his status as a citizen – as an autonomous individual endowed with rights and obligations not contingent upon affiliation with any particular group, whether ethnic or religious. Therefore, Spinoza not only fully embraced his excommunication (ḥerem) from the Jewish community of Amsterdam but also staunchly rejected adopting any other religious allegiance. His departure from Judaism foreshadowed modern secular forms of life. By demonstrating the possibility of leading a meaningful life outside the bounds of Judaism, Spinoza inadvertently presented modern Jews with the challenge of grappling with the contemporary relevance of Jewish identity and tradition. Consequently, the history of modern Jewish thought can be perceived as a story of redefining the meaning and significance of Jewishness vis-à-vis the immanent revolution – or to phrase it differently, of internalizing Spinozistic principles and modern values without becoming a Spinoza (cf. Smith 1997; Schwartz 2012).

In this manner, Spinoza’s work laid the groundwork for a distinctive aspect of Jewish modernity: a wide spectrum of Jewish modes of existence. While multiple historical processes contributed to this extensive diversity, three, in particular, warrant attention: emancipation, historicism, and nationalism (Eisen 1999; Ben-Rafael 2002; Batnitzky 2011; Goodman 2020). The prospect of political emancipation – the granting of citizenship to Jews within their respective countries – prompted the erosion of their centuries-old social and cultural autonomy or relative isolation. Consequently, questions arose regarding the extent to which accommodation to modernity should be permissible. Concurrently, the emergence of critical historical consciousness – particularly the acknowledgment that all cultural (read: religious) institutions are time-bound and hold relative significance in history – challenged the absolute status of traditional norms and worldviews (Yerushalmi 1982). As a result, different sensibilities and priorities gave rise to diverse patterns of religious accommodation, such as Reform, Conservative, Neo-orthodox, and Ultra-orthodox Judaism (Sacks 1993; Hartman 2007). Moreover, the surge of modern nationalism fostered a division between the Jewish people and their religion, thereby promoting Jewish identities that are not religious, but rather cultural, social, or existential. These secular manifestations include Jewish cosmopolitanism, which disassociates Jewishness not only from religion but also from peoplehood, committing itself – as a Jewish calling – to a distinct universal vision or vocation (Novak 2006; Gelbin and Gilman 2017).

In the midst of the emergence of such a diverse array of Jewish identities, two distinct attitudes toward this plurality of options have surfaced. One stance is held by those who embrace a specific mode of Jewish life while regarding other modes as flawed and incompatible with their fundamental understanding of Jewishness (or as valid choices for other Jews but not for themselves). The alternative stance is adopted by those who embody multiple modes of Jewishness without aligning themselves with any particular group (and some of them even fluctuate among various configurations). Regardless of the stance taken, the issue is intricately linked to the question of whether and to what extent Judaism can accommodate the individualistic premise of modern times. Specifically, this premise asserts that our lives derive meaning only through self-expressive liberty and individual freedom, and that ideal societies should not only permit but also promote such self-expression and individuality.

Let me illustrate this diverse spectrum of approaches, especially concerning the understanding of divine oneness, by examining two sets of Jewish thinkers: The first set comprises secular Jews, while the second set consists of religious Jews.

Freud and Frankl

The first pair consists of Sigmund Freud (1856–1939) and Viktor Frankl (1905–1997), both Austrian psychiatrists and self-identified Jews. Freud, renowned as the father of psychoanalysis, stands as one of the most influential thinkers of the twentieth century. In contrast, Frankl, a survivor of Nazi death camps, founded a meaning-centered psychotherapy called “logotherapy.” While both Freud and Frankl lived as secular Jews in a secular world, they approached the category of divinity and divine oneness in markedly different ways. This contrast largely arose from their perspectives on the secular idea of immanence – Fraud tended to accept it unquestioningly, while Frankl sought to qualify it.

A “Godless Jew”

Freud, who referred to himself as a “Godless Jew,” staunchly identified as an atheist, determined to live a life guided by ethical principles and to reject all religious beliefs as mere illusions (Gay 1987; Yovel 1989: vol. 1, 136–166; Flem 2016). Although both of his parents hailed from Orthodox backgrounds, Freud not only abandoned the religious practices of his family but also embraced and thrived within the secular culture surrounding him. While marrying Martha Bernays, an Orthodox Jewish woman and granddaughter of the chief rabbi of Hamburg, in what turned out to be a loving and harmonious union, Freud refrained from allowing any religious rituals, including the basic act of lighting Sabbath candles, to be performed at home. Nevertheless, he proudly maintained his Jewish identity, attributed his later success to his Jewish heritage, and consistently demonstrated unwavering solidarity with the Jewish people (Simon 1957; Yerushalmi 1991). Furthermore, in the preface to the Hebrew translation of Totem and Taboo (1930), Freud acknowledged his estrangement from “the religion of his ancestors – as well as from every other religion” and then posed a rhetorical question to himself: “Since you have abandoned all these common characteristics of your compatriots, what is left to you that is Jewish?” To which he responded: “A very great deal, and probably its very essence” (Yerushalmi 1991:14).

Freud shared Spinoza’s naturalistic determinism, asserting that all facets of inner life – whether emotional, intellectual, artistic, or religious – are rigidly governed by the principle of causality. To Freud, religion served primarily a defensive fantasy, originated from existential anxiety and a longing for security and protection. At its core, its purpose was to provide solace and encourage renunciation, promoting adherence to religious ideals and precepts for the benefit of society. He viewed the concept of God, along with associated religious doctrines, as imaginative constructs developed to manage repressed desires and existential questions. Essentially, Freud regarded religion as a form of infantile mass neurosis – an illusionary construct that obscured genuine existential needs and fears with sanctified categories. This, in his view, led to a form of false consciousness or alienation, hindering the resolution of actual problems in their own terms. Historically, Freud speculated, based on anthropological data and his Oedipus Complex theory, that the traumatic murder of an alpha male figure was presumably, and repeatedly, committed in many places in the primeval period, and that the accumulation of feelings of guilt and patterns of coping with the sense of remorse led to the formation of the supreme father-God figure and its corresponding religious traditions (Yovel 1989: 136–166; Capps 2001; Pals 2021: chapter 2).

Moses and Monotheism

In his final years, Freud delved into topics that had long intrigued him: the nature of Jewish identity and the roots of antisemitism. This inquiry culminated in his final book, Moses and Monotheism (1939), which was published just before the onset of the Holocaust. While the book sparked intense reactions from both Jewish and non-Jewish communities, those versed in the academic discourse of the time would readily acknowledge that much of its supporting evidence was not entirely groundbreaking. Instead, its novelty lay in the innovative amalgamation of preexisting studies and hypotheses (Kaufmann 2017b [1940]).

Three antecedent studies significantly influenced Freud’s work:

1. (1) The archeological findings concerning Pharaoh Amenhotep IV: Also known as Ikhnaton, this monarch promoted a short-lived religious reform, abolishing the traditional religious rites of Egypt in favor of the exclusive worship of the sun-power, Aton, as the sole universal deity and sustainer of all creation.

2. (2) The thesis proposed by German biblical scholar Ernst Sellin regarding the tradition surrounding the supposed murder of Moses: Sellin suggested that the book of Hosea reflects a tradition wherein the Israelites murdered Moses and abandoned his religion before reaching the Promised Land.

3. (3) Freud’s own psychoanalytical theory of religion: Central to this theory is the concept of the murdered father-figure, which, in Freud’s view, aids in our understanding of the origins of religion.

Freud also resorted to the documentary hypothesis of the Pentateuch and considered other philological studies. For instance, he referred to the etymology of Moses’ name, “Mose” in Egyptian, signifying “son” or “born.” This name component also features in various Egyptian names, such as Thut-mose, Amen-mose, and Ptah-mose.

The gist of Freud’s thesis can be summarized as follows: Moses, according to Freud, was not an Israelite but a native Egyptian and follower of Ikhnaton. To preserve the Aton religion, which Freud suggests may have partly originated from the Near or Far East, Moses introduced it to an oppressed Hebrew tribe in Egypt, leading them out of bondage and establishing a new nation based on that belief. Its doctrine included the abstract concept of one God, the rejection of all magic ceremonies, and the demand for a life of truth and justice, renouncing instinctual and sensual gratification in favor of spiritual and intellectual aspirations. However, this religion proved too lofty and demanding for the vulgar mass of erstwhile slaves who soon rebelled Moses, ultimately resulting in his murder. Despite attempts to suppress the memory of this act, feelings of guilt persisted among the Hebrews and resurfaced centuries later as a disguised yearning and devotion to the singular God, perceived as the revered father-figure. This devotion transformed the Jews into a highly ethical and intellectual people, characterized by a distinct sense of chosenness, or what Freud termed “self-confidence.” For Freud, the essential nature of Jewish identity lay not in belief in divine oneness, which he believed was not of Jewish origin, but in the intellectual, ethical, and personal qualities that emerged through its adaptation. Furthermore, Freud drew parallels between the murders of Moses and Jesus, viewing them as keys to understanding Christian antisemitism. He attributed this phenomenon to unconscious drives and displacement, including jealous rage over Israel’s spiritual birthright, the uncanny impression of circumcision and castration anxiety, and the ancestral heritage of a repressed grudge against forced conversion into Christianity.

Initially, Freud’s work was severely criticized or was otherwise ignored altogether within Jewish circles. Martin Buber labeled it “unscientific” and “regrettable,” while Leo Strauss described Freud as “not knowing anything of the [religious] experience in question.” An anonymous critic from Boston even wrote to Freud: “It is regretted that the Gangsters in Germany did not put you into a concentration camp, that’s where you belong” (Gay 1987: 149). However, over time, his work has garnered serious scholarly attentions, not only for its insights into Freud’s Jewish interests or the modern Jewish condition, but also for its contributions to understanding collective memory, group identity, national traumas, and cultural phenomena. It is now often hailed as “one of Freud’s finest achievements” (Ginsberg and Pardes 2006: 1). In the field of ancient history as well, its significance has been revisited by a world-leading Egyptologist, as well as by some prominent Jewish biblical scholars (Bernstein 1998; Ginsberg and Pardes 2006; Feldman and Sharvit 2018). While appreciations of Freud’s work may fluctuate, one aspect remains clear: in this “godless” outlook, God is not one – God is zero.

Frankl’s “Third School” and Its Jewish Background

Frankl, on the other hand, is renowned for developing logotherapy, a therapeutic method emphasizing the will to meaning as the primary motivation in human life. This approach, known as the “Third Viennese School” of Psychotherapy, does not seek to replace the two antecedents – the Freudian and the Adlerian – but rather complements them by addressing an oft-neglected aspect of human existence: existential concerns. Logotherapy posits that neuroses can arise not only from instinctual frustrations (Freud) or inferiority feelings (Adler) but also from existential frustration or a sense of emptiness.

In other words, what matters is not only the instinctual drives or the feelings about self-ideal, but the stance we take toward them. Logotherapy thus focuses on aspects such as conscience, reflectiveness, and meaning-making, which Frankl calls the noölogical or “spiritual” dimension of human existence. Here, the term “spiritual” is used not in a religious sense but rather to refer to the “specifically human dimension” (Frankl 2010: 62). Frankl asserts that the use of this term, and logotherapy itself, are based on the philosophical anthropology and existential studies of phenomenological thinker Max Scheler (Frankl 1969: 10; Frankl 2010: 50, 127, 159).

Frankl’s key conviction, which he substantiates through his personal experience in Nazi concentration camps, is that life can provide meaning under any circumstances. He argues that we can transform personal tragedies into human triumphs, citing Nietzsche: “Whoever has a why to live for can bear almost any how” (Frankl 2014: 97). According to Frankl, it is not we who are to ask about the meaning of life (“What can I expect from life?”) but it is life that asks the questions and we are the ones who must answer (“What does life expect of me?”; “What task in life is waiting for me?”). In this regard, Frankl draws our attention to the self-transcendent quality of human reality as the essence of human existence (Frankl 2000: 89–90; Frankl 2010: 144–45, 177). That is, only to the extent to which we live for purposes beyond ourselves – “toward meanings to fulfill, or toward other human beings to encounter lovingly” – are we really becoming human and actualizing ourselves (Frankl 1986: 294). Hence, Frankl remarks, the pursuit of happiness and self-actualization – which is the driving ethos of modern societies – is misguided and must be reversed: “Happiness is not only the result of fulfilling a meaning but also more generally the unintended side effect of self-transcendence. It therefore cannot be ‘pursued’ but rather must ensue” (Frankl 1986: 297; Frankl 2000: 89–90).

The question of whether and to what extent Frankl’s theory has Jewish roots remains a matter of contention (Bulka 1979; Schweid 1994: 85–142). Frankl comes from an observant liberal family, and his maternal ancestors include the prominent sage “Maharal of Prague” (Judah Loew ben Bezalel; c. 1525–1609), as well as the greatest traditional commentator of the Bible and Talmud, Rashi (Rabbi Solomon ben Isaac; 1040–1105). However, Frankl’s formative milieu is generally secular, and his knowledge of Judaism may largely be originated from secondary sources, such as Martin Buber’s writings, whose influence on Frankl is hardly missed. True, one of the towering figures of German Jewry, Leo Baeck (1873–1956), is said to have referred to logotherapy as “essentially Jewish” (Frankl 1969: 143, n. 2). Furthermore, Frankl not only draws upon his Jewish experiences and wisdom but also comments on Jewish antecedents to some of his key ideas – for example, on Maharal that “in fact, he was a precursor to what I call dimensional ontology” (Frankl and Lapide 2014: 58; my translation). Nevertheless, Frankl intends to present logotherapy not as a Jewish project or a Jewish contribution to humanity, but rather as a critical method grounded strictly on empirical foundations and general anthropological principles.

The Unconscious God and Human Oneness

For Frankl, religion is a distinct category that concerns itself with the ultimate questions of life, death, and suffering. Unlike other psychotherapists of his era who espouse the immanent conviction, Frankl acknowledges the transcendent dimension of reality. He opposes reductionist views that regard religion merely as a reflection of unconscious needs or fantasies. This stance, for which logotherapy is often (mis)labeled as “religious,” is not rooted in dogma but in an analytical premise: Religion pertains to a dimension of human existence that is distinct from the somatic and psychic dimensions. Thus, reducing the former dimension to a mere epiphenomenon of the latter dimensions diminishes the humanness of human nature. At the same time, Frankl maintains a clear boundary between psychotherapy and religion, leaving each patient to decide how to relate to the category of religion. This is because Frankl regards the aim of psychotherapy as the healing of the soul, not its salvation, which is the domain of religion.

Frankl asserts that humans possess not only an instinctual unconscious but also a “spiritual unconscious” – that each person has a latent intuition and unconscious relation to the transcendent. This inherent religiosity may surface, particularly in response to what he calls the “‘tragic triad’—pain, guilt, and death” (Frankl 2000: 123, 142). During such moments, individuals may feel accountable before a “transcendent Thou,” whose presence previously remained unrecognized and unconscious (thus, Frankl’s term: an “unconscious God”). Moreover, Frankl contends that we may encounter this transcendent referent not only through interpersonal but also through intra-personal dialogues, as “the partner of our most intimate soliloquies” (Frankl 2000: 151).

Frankl posits that conscience has a transhuman dimension, serving as a mediator of transcendence. He argues that this dimension cannot be reduced to the superego or human subject because it can contradict these categories. Here, too, Frankl takes a critical stance against the Zeitgeist of his day, which tends to reduce conscience to its psychological facticity, neglecting its transcendent dimension. Furthermore, he warns that suppressing religious feelings can exacerbate, rather than alleviate, noögenic neuroses that derive from existential concerns. Frankl therefore suggests that we might better consider flipping Freud’s idea of religion as “universal compulsive neurosis of humankind,” and, conversely, regard compulsive neurosis as “diseased religiousness” – that is, our repressed religiousness turning, as it were, “the angel in us” into “a demon” (Frankl 2000: 75).

Finally, we can turn to divine oneness in Frankl’s work. He discusses it in relation to human survival, and he does so in three different contexts: the individual, the ecumenical, and the universal.

Shortly after arriving at Auschwitz, Frankl had to surrender his clothes along with his most precious possession – a book manuscript of logotherapy, his life’s work, which he hid in the inner pocket of his fine coat. He then took over a worn-out coat of an inmate who had already been gassed. In its pocket, he found a leaf torn from a prayer book containing the passage of the Shema, stating belief in one God. In Frankl’s words: “How else could I interpret this ‘coincidence’ than as a challenge to me to live what I had written, to practice what I had preached?” (Frankl 1997: 94; cf. Frankl 2014: 108). It was a moment, for Frankl, to find himself responsible before his “transcendent Thou,” calling him to be a living testimony to his own thesis that the will-to-meaning has survival value for the human individual. I, for one, wonder if, in that context, Frankl also construed the triadic phrase in the Shema – “with all your heart, with all your soul, and with all your might” (Deut 6:5) – as corresponding to the triad in his multidimensional conception of human existence: the psychic, the spiritual, and the somatic, respectively.

Regarding the ecumenical survival – and here “ecumenical” in the broader sense of the Abrahamic religions – Frankl addresses how different religions and denominations can coexist without compromising their own religious commitments. The key, in his view, is that they all develop awareness towards what he calls the “ultimate commonality of the common ultimate,” that is, the “monism of monotheisms.” In this regard, he suggests they all expand their horizons and recite the Shema in the following sense: “Hear, all you peoples (all monotheistic denominations): our (denominational) God is one and the same!” (Frankl 1947: 48; my translation).

Frankl also discusses the awareness of divine oneness in relation to the universal survival of humankind. However, he regards this awareness as a preliminary stage, urging us to progress further. In his words: “What we need is not only the belief in the one God but also the awareness of … one mankind, the awareness of the unity of humanity” – this he calls “monoanthropism.” He emphasizes that hope for this universal survival lies in peoples embracing “monoanthropistic convictions” – only if they are all united by the awareness of common meanings and shared responsibilities, that is, “common denominators in what they feel makes their lives worth living” (Frankl 2000: 135; Frankl 2010: 149). In fact, this awareness – and the resulting sense of solidarity – is vital not only for the survival of humanity but also for the survival of our humanness. For only through dialogical interaction with others can we cultivate our responsibleness and actualize our humanness as moral agents. As Frankl sees it, herein also lies an antidote to the dehumanizing potential of modern liberal societies – where “freedom threatens to degenerate into arbitrariness unless it is lived in terms of responsibleness” (Frankl 2010: 146).

Kaplan and Heschel

The next pair comprises Mordecai M. Kaplan (1881–1983) and Abraham Joshua Heschel (1907–1972), both immigrants from Europe to the United States and towering figures of modern Judaism. They were both well versed in two different kinds of worlds – traditional and modern – and also each endowed with two different kinds of rabbinic ordinations – orthodox and liberal. Kaplan was a radical rationalist, educator, and founder of what is known today as Reconstructionist Judaism, whereas Heschel was a dialogical thinker, prolific writer, and religious activist. Kaplan and Heschel viewed modern life in liberal society (read: in the United States) – especially, its propensity toward excessive individualism, expediency-mindedness, and this-worldliness – as a critical challenge to Judaism, because modern Jews now had a choice to be integrated into the greater civilization without retaining their cultural heritage and spiritual identity. While Kaplan and Heschel differed in outlook, they respectively sought to breathe new life to their tradition and validate its vital significance to modern life and to the survival of humanity more broadly.

Modernistic Revitalization of Judaism

Born in 1881 to a family of a Talmudic scholar in Lithuania, then the world’s major center of rabbinic learning, Kaplan immigrated to the United States with his family at age nine. At home, for many years, Kaplan studied Talmud and other rabbinic texts with his father. While pursuing degrees in secular subjects – such as philosophy, sociology, and education – at the City College of New York and Columbia University, he also received his rabbinical ordination from the Jewish Theological Seminary of America. Several years later, during a brief visit to Europe, he acquired another ordination from the preeminent orthodox rabbi Isaac Jacob Reines (1839–1915). Upon returning to New York, Kaplan served at the Seminary, first as principal of its Teachers Institute and later as professor of homiletics and philosophies of religion. A pious rationalist, he was said to be the only member of the faculty who would open his classes with prayer. A religious naturalist, he rejected supernatural notions of miracle, preferring to find wonder in everyday occurrences such as the birth of his grandchildren or the exchange of goods and services through his teaching, namely, of giving the world “three hours of homiletics” and the world giving back a “nourishment lunch” (Scult 2014: 117, 221). A free thinker, he admired Spinoza’s modernism and idea of “blessedness,” which Kaplan thought corresponded to his own notion of “salvation.” In Kaplan’s words: Spinoza “identified salvation with the fulfillment of that which constituted human nature, which for him consisted in a life of the body and of the emotions in the service and under the control of reason” (Scult 2014: 21). A committed educator, Kaplan challenged the status quo of modern Jewry, provoked newer generations into action and renewal, and saw himself as assuming the Socratic role of communal “gadfly” (Waxman 2010: 42).

Kaplan’s aim was to ensure the viability of Judaism within a modern democratic, pluralistic society. He deemed the Jewish civilization to be compatible with, yet distinct from, the secular majority civilization. Termed “cultural hyphenism” by Kaplan (1934: 215–218, 248–251, 515–516), this stance asserted that being a good Jew could enhance, rather than hinder, one’s ability to be a good citizen. According to Kaplan, cultural affiliation was not opposed to individualism; instead, it offered a framework of meanings and values essential for leading a meaningful individual life. By advocating this perspective, Kaplan provided modern Jews with an approach to maintaining their Jewish distinctiveness while actively engaged in contemporary civic life (Waxman 2010: 11–14, 72).

As a religious modernist, Kaplan sought to counter the challenge of assimilation and called for the “reconstruction” of Jewish life to align with the concerns of modern Jews. Thoroughly expounded in his magnum opus Judaism as a Civilization (1934), he conceived of Judaism as an “evolving religious civilization” that encompasses all aspects of individual and collective life, hence, irreducible to a set of religious beliefs and ritual practices. He identified three basic steps in the formation of Jewish identity: starting with “belonging” to the Jewish people, then “behaving” according to Jewish practice, and finally, “believing” according to Jewish religion. He therefore advocated for transforming synagogues into community centers – a vision partially realized in the form of Jewish Community Centers worldwide – which would serve not only as a place for worship but also for learning, recreation, and communal life more broadly. Kaplan viewed the history of Jewish theology and ritual practice as an ongoing quest for meaningful existence, necessitating continual revaluation and readjustment of traditional categories to align with evolving human thought and normative sensitivity. For example, in coediting the Sabbath Prayer Book (1945), he retained most of the words and structure of the traditional liturgy but replaced statements that would not resonate with modern egalitarian sensitivity and scientific worldview, such as the notion of the Jews as the chosen people, resurrection of the dead, and the doctrine of a personal Messiah. Additionally, he introduced the bat mitzvah ceremony in the early 1920s as a counterpart of the bar mitzvah, marking a young woman’s rite of passage. Kaplan was ahead of his time in many regards, and his ideas left a lasting imprint, in one way or another, on the institutional and ideological landscapes across all segments of American Jewry: Reform, Conservative, Orthodox, and secularist.

Kaplan was also an ardent Zionist. He envisioned modern Israel as a vibrant cultural center for the world Jewry, describing it as a “radical solution to the problem of the future of the Jewish people” (Kaplan 1960: 391). This “problem” encompassed the loss of collective identity due to persecution and assimilation, as well as the decline of cultural creativity stemming from stagnation and irrelevance. Kaplan held the survival and enhancement of Jewish life worldwide as the ultimate goal, with the state of Israel serving as a means to achieve it (Goldsmith and Scult 1985: 26). Furthermore, he advocated for the equality and interdependence of Israeli and Diaspora Jewry in Jewish life, opposing the Zionist rejection of the Diaspora (Kaplan 1956: 393–411; Kaplan 1970: 116–135). In other words, he saw Israel and the Diaspora as complementary entities, each contributing to the Jewish people’s role as a “light to the nations.” Kaplan also asserted that the success of modern Israel hinged upon peaceful coexistence with local Arabs and other ethnic and religious residents (Cohen 1990).

The following point should not go unnoticed: While many consider Kaplan as the ideological founder of the Reconstructionist Movement, Kaplan himself did not initially intend to establish a new movement or denomination. Instead, his goal was to create a platform for greater unity among the Jewish people. While maintaining traditional ritual practices, Kaplan firmly rejected the notion that there is only one way to be Jewish. He regarded, Judaism as a comprehensive civilization, inherently and ideologically pluralistic. In short, Kaplan transcended denominational boundaries and meant to serve the entire Jewish community (Kaplan 1956: 441, 447).

Religious Naturalism and Ethical Universalism

Kaplan’s theology is a brand of religious naturalism – or “supra-naturalism” as he calls it – which defines God as “the process that makes for salvation,” rather than as a supernatural self volitionally involved in human life. Here, “salvation” is tantamount to progressive approximation towards the ideal of perfection, both individually and collectively, representing “whatever we can conceive as maximum fulfillment of the highest possibilities of human nature” (Scult 2014: 160). Kaplan advisedly uses the term “process” for his God-idea to avoid the tendency to reify, or thingify, God – he did not want to identify God as an object or entity. For Kaplan, there is no personal God; hence, revelation cannot be perceived as a divine communication in any traditional sense. Rather, it is viewed as a human discovery of, or exposure to, God as a Cosmic Process. The same holds true for prayer. According to Kaplan, prayer should not be seen as a form of address but rather as a means of elevating one’s consciousness, a pathway to activate one’s higher creative self in pursuit of self-fulfillment.

As for divine oneness, Kaplan approaches it from a historical and functional standpoint. Historically, it has developed through three pivotal revolutions: The first, led by Moses, reduced the multitude of deities to a single God; the second, championed by medieval philosophers, shifted the perception of God from corporeal to incorporeal; the third, advocated by Spinoza, changed thinking from the God of miracles to the God of nature. In this regard, Kaplan not only regards Spinoza as having “achieved the highest conception of God,” but also views his own naturalistic theology as a variation of Spinoza’s worldview (Scult 2014: 7–27). Functionally, on the other hand, Kaplan stresses the vital importance of God’s unity in moral formation. He asserts that understanding this unity enables us to perceive order in the moral world, and, furthermore, to seek both individual self-integration and collective unity for achieving ethical wholesomeness (shalom). As for the opening of the Shema (Deut 6:4–5), Kaplan construes it not as a statement about God’s essence, but as a pledge of exclusive allegiance to God – a call to recognize and align oneself to the cohesive unfolding of the Cosmic Process underlying the manifest complexities of human life and reality.

Furthermore, Kaplan firmly rejects any assertion of Jewish superiority, let alone monopoly, on the belief in divine oneness. He states: “If monotheism is the truth, and it is the truth, it is not confined to Judaism. It is not our mission to teach monotheism to the world” (Scult 2014: 95). According to Kaplan, other religions can also comprehend the working of this universal process and express it in their own terms, which can then be translated into the language of different religious traditions. Kaplan’s religious pluralism thus extends to all faiths: “All may contribute equally, though in different ways, to the establishment of God’s universal kingdom of righteousness” (Kaplan 1956: 427).

For Kaplan, it follows, the modern Jewish condition of dual existence – of “living in two civilizations” – is both a challenge and an opportunity. It presents a challenge in that modern Jews may find themselves at times poised between the two worlds, or even alienated from both. However, it also offers an opportunity for existential and moral growth. Kaplan sees the modern world as encouraging an exchange of ideas and experiences with people of other religious and cultural backgrounds, which he considers indispensable for such growth and peaceful coexistence. In other words, for Kaplan, Judaism is not an end in itself but rather a means toward becoming more fully human, a means to live in partnership with others, whether Jewish or non-Jewish, thereby bringing humanity closer to the fulfillment of its ideals.

A Modern Biblical Voice

Born in Warsaw into a Hasidic dynasty in 1907, Heschel made a quantum leap from the traditional Jewish world to the modern landscape of Europe (Dresner and Kaplan 1998). Having achieved mastery of the Jewish religious heritage and obtaining rabbinic ordination in his hometown, he initially pursued a literary career in poetry among secular Jews in Vilna. He next moved to Germany, where he enrolled at the University of Berlin to study philosophy while attending a modern liberal Jewish institution. During his time at the university, he wrote his doctoral thesis on the biblical phenomenon of prophetic consciousness, while at the Jewish institution, he gained critical tools for Jewish Studies and earned a rabbinical degree. Fleeing the Nazi onslaught, Heschel sought refuge in England before immigrating to the United States. In the US, he first taught at the Hebrew Union College in Cincinnati and then at the Jewish Theological Seminary in New York, where he crossed paths with a series of Jewish intellectuals, including Mordecai Kaplan. Concurrently, Heschel emerged as one of the most preeminent religious thinkers of his day. As a prolific author, he wrote on diverse subjects, including religious poetry, critical studies of classical Jewish sources, a general philosophy of religion, and contemporary social and existential issues; as a distinguished activist, he played a leading role in the civil rights movement, advocating against the Vietnam war, and engaging in Jewish-Christian interfaith dialogue, among others, influencing discussions around the Second Vatican Council. While deeply engaged in the modern world, he maintained a steadfast commitment to traditional practice and Hasidic spirituality.

Much of Heschel’s writings and activism can be seen as an attempt to broaden the contemporary scope of epistemic and normative outlook by reintroducing biblical and Jewish thought as a response to existential questions. From his standpoint, the foundational premises of modern Western thought predominantly stem from Greek rather than Hebraic thinking, which historically has been underappreciated due to the influence of, among others, Spinoza (Heschel 1955: 24). Consequently, Heschel sought to foster a sense of openness to the dimension of reality that surpasses the horizon of immanence, a dimension often overlooked or marginalized in modern discourse.

Regarding the State of Israel, Heschel’s commitment was primarily spiritual. To him, Israel reborn was as much a “repudiation of despair” as it was a “renewal of trust in the Lord of history,” calling for the establishment of the land to be a “seat of mercy” for all humanity (Heschel 1967: 37, 133, 134). Hence, he argued that the mere self-preservation of the Jewish people was an “inadequate motivation” for the existence of Israel. In contrast to Kaplan and others, Heschel regarded the Jewish state not as a “solution” to Jewish questions but rather as a “challenge” to many of the purported answers to both Jewish problems and humanity’s ultimate questions. In light of the post-Auschwitz and Hiroshima world teetering on the brink of self-destruction, Heschel perceived the ultimate meaning of the Jewish state in alignment with the “vision of the prophets” – namely, the redemption of all fellow humans. This vision, claimed Heschel, would remain unrealized unless all of us – Jews and non-Jews – were willing to actively participate in its realization (Heschel 1967: 219–226; cf. Eisen 1986: 169–172).

The Living God

According to Heschel, the fundamental premise of biblical thinking is that God is in search of human partnership, that God is a God of pathos who is concerned with human destiny and cares about the world to the extent of experiencing divine suffering. In this outlook, we are called to recenter our subjectivity from the self to God, thus recognizing that God is the subject of whom we are the object. Heschel’s God – as distinguished from Aristotle’s Unmoved Mover which remains silent, hidden, and self-sufficient – is aptly referred to as the “Most Moved Mover” (Rothschild 1959: 25). Implicitly rejecting Maimonides’ abstract and Hellenized concept of divinity, Heschel endeavors to restore the reality of the biblical God, free from the centuries-old Greek metaphysical assumptions. No less important, Heschel’s choice of a poetic and evocative writing style, over an argumentative form, stems from his theological aim not merely to impart information but to inspire transformation – to re-awaken a sense of wonder in his readers and foster a radical awareness of the divine presence in their lives. It is no surprise that his writings have served as a source of spiritual guidance for many seekers, Jewish and non-Jewish alike.

Here, the category of self-transcendence may be useful for explicating Heschel’s perspective on both divinity and humanity (Held 2013). In Heschel’s theology, God stands as the sole being surpassing the constraints of ego and self-interest, thereby possessing the capacity to wholly attend to the needs of creatures. Likewise, within Heschel’s anthropology, the supreme dignity of being human entails a commitment to self-transcendence: to be fully human, one must shift from self-centeredness to other-centeredness, fostering an attunement to the existential needs of both divine and human personalities. Heschel’s stress on self-transcendence extends to his critique of modernity and its maladies, particularly the exploitative mindset and behaviors, the allure of conceit and sense of self-enclosure, nihilistic philosophies that dismiss human effort or life itself as meaningless. Here, Heschel’s notion of being human – the need to be more than human in order to avoid being less than human – resonates profoundly with Frankl’s notions of humanness and self-transcendence discussed earlier. While it is conceivable that one thinker influenced the other, it is equally plausible that both draw from a shared source, such as Max Scheler, whose phenomenological analysis of sympathy greatly shaped Heschel’s thesis on prophetic consciousness (Rotenstreich 1974).

It should be evident by now that Heschel’s theological stance diverges markedly from Kaplan’s. In fact, Heschel frequently states that the experience of revelation should not be construed solely within the impersonal framework of “process” but rather understood as the interpersonal encounter or “event,” implicitly repudiating Kaplan’s viewpoint (Heschel 1955: 209–212; Heschel 1962: 426–446). Stated differently, while Kaplan moves away from the traditional notion of God as the revealer, Heschel affirms the fundamental truth of the biblical assertion that God spoke to people – whether verbally or metalinguistically – although Heschel acknowledges that this assertion presents a “challenging, embarrassing, and overwhelming claim” (Heschel 1996: 385). Moreover, Heschel disagrees with Martin Buber who regards revelation as a “vague encounter” (in Heschel’s wording) or a disclosure of God’s presence without content. In Heschel’s view, “A Jew cannot live by such a conception of revelation. Buber does not do justice to the claims of the prophets. So I have to choose between him and the Bible” (Heschel 1996: 385).

Divine Oneness: Its Semantic and Existential Meanings

Now to Heschel’s approach to God’s oneness. Semantically, he understands it in three distinct senses: being unique, only, and the same. Being unique, in that God is utterly different from any other being in the world. Being only, in that God alone is truly real while everything else is contingent and ephemeral. Being the same, even though God can manifest through a limitless range of divine attributes and revelatory forms (Heschel 1951a: 114–119).

Existentially, on the other hand, Heschel identifies the significance of God’s oneness on multiple levels. First, its appreciation can recenter one’s focus from the world and the self to the one true God fostering a vital sense of awe and transcendence (this shift is vividly illustrated in Heschel’s recollection of his time in Berlin and the transformative experience of reciting the Shema; Heschel 1996: 130–131; cf. also Heschel 1951a: 107–123). Second, its awareness can serve as a basis for human solidarity, reinforcing the notion that all individuals are equally encompassed with God’s care for humanity. According to Heschel, recognizing our shared status as children of the same divine Parent underscores the essential “brotherhood” of humanity, asserting that this bond “would be an empty dream without the fatherhood of God” (Heschel 1951a: 112; Heschel 1996: 238). Thirdly, its attunement can also facilitate interreligious partnerships, as it can lead different faith traditions to the recognitions conducive to the formation of genuine ecumenical alliances: that their understanding of the ultimate truth always remains partial, tentative, and incomplete; that the all-inclusiveness of the transcendent reality contradicts the exclusive claim of any particular religion; and, therefore, that there may be a way to foster reverence for other traditions without compromising loyalty to one’s own tradition (Heschel 1996: 235–250). Relatedly, Heschel also warns that making religion an end, rather than a means, is a violation of divine oneness. As he states: “To equate religion and God is idolatry” (Heschel 1996: 243). Equally significant, his theological writings manifest a profound conviction that none of us can claim monopoly on the transcendent oneness whose presence fills the whole earth, for, as Heschel puts it, “it is within our reach but beyond our grasp” (Heschel 1955: 83). Here, the reader may find his locution, along with the religiosity it encapsulates, strikingly reminiscent of Ibn Paquda and Halevi, hence, also of Sufi thinkers.

*

Unlike Kaplan, Heschel thinks of Judaism not, or not only, as a form of civilization but as an art of surpassing all kinds of human civilization (Heschel 1951b: 26–32; Heschel 1955: 417–419). Whereas for Kaplan, the primary focus is how modern Jews can live in two civilizations, Heschel’s overriding concern lies elsewhere – namely, how modern people, Jewish and non-Jewish alike, can live in two realities, immanent and transcendent, and what together we can do for the sanctification of humankind.

Conclusion: “Who Knows One?”

There’s nothing quite as frightening as someone who knows they are right.

Michael Faraday

A Kaleidoscopic Testimony or the Rashomon Effect?

One of the liturgical proclamations that explicitly state the Jewish obligation to God’s oneness is called Aleinu (“It is our duty [to praise]”). This proclamation, consisting of two paragraphs, is recited today as the concluding statement for all liturgical services. The first paragraph addresses Jewish particularity in the present world, with Israel worshiping the One God while others worshiping idols. It speaks directly to other Jews in the first person plural, while referring to God in the third person (e.g., “we bow in worship and thank the King of kings, the Holy One ever to be praised, who extends the heavens and establishes the earth”). This paragraph emphasizes the Jewish commitment to praising the only true God, concluding with the most explicit statement of God’s oneness in biblical scripture: “Know therefore this day and keep in mind that YHWH alone is God in heaven above and on earth below; there is no other” (Deut 4:39). Some phrases in this paragraph have often been construed as derogatory toward other religions and peoples, hence they are sometimes omitted or altered. The second paragraph expresses hope for the future world, still addressing to other Jews in the first person plural but now referring to God in the second person, as if the speaker and other Jews were all standing in the very presence of the one true God (e.g., “we place our hope in You, YHWH our God, that we may soon see the glory of Your power”). This paragraph speaks of universal recognition of God by all humanity as a form of tikkun olam or “repairing the world” under divine sovereignty. It concludes with an all-encompassing prophetic aspiration for divine oneness: “Then YHWH shall be king over all the earth; in that day YHWH shall be one with one name” (Zech 14:9). Both paragraphs begin with the same letter (‘ayin) and conclude likewise with the same letter (dalet). Taken together, these letters form the Hebrew word for “witness” (‘ed), thus the proclamation reaffirms the Jewish commitment to serve as a living witness to the one true God. It is no wonder that Aleinu is often associated with martyrdom (cf. Greek martus “witness”). For example, the martyrs of Blois in 1171 sang the proclamation as they were burned to death. However, how these and other countless Jewish martyrs understood the content of their witness remains a matter of speculation. This is because – I can only reiterate what I stated at the outset – what persists in the Jewish tradition is not a shared understanding of God’s oneness but a shared commitment to the reality of that oneness, regardless of how its content may be interpreted.

Recapitulation

To recapitulate some of the key points we have covered thus far: I have divided Jewish history into four phases – biblical, rabbinic, medieval, and modern – and explored diverse models for conceiving the reality of divine oneness.

In the biblical phase, God is consistently experienced and depicted as a relational subject – always the living God and never an abstract principle or process. What distinguishes biblical concepts of divine oneness is the qualitative (rather than numerical) oneness of its deity: the absolute supremacy of YHWH as the one and only. Therefore, insofar as this premise is not compromised, biblical authors have no reservations about acknowledging the existence of other celestial beings.

In the rabbinic phase, while the understanding of God as a relational subject generally remains intact, the category of divine oneness meets new challenges. With the focal point of Jewish life shifting from the sanctuary to scripture (due to the destruction of the Jerusalem Temple and the canonization of scripture), rabbinic forms of piety, which prioritize Torah study as the primary religious duty, become mainstream in Judaism. The significance of scripture is so emphasized that it often appears to assume much of God’s place in rabbinic consciousness. This dynamic creates a certain level of internal tension or duality between God and Torah within the theological framework of divine oneness – not unlike the Christian binitarianism of God and Jesus Christ. Equally significant, life under gentile rule necessitates that the Rabbis address the issue of political idolatry: To what extent they can accept the legitimacy of non-Jewish authority, without compromising their allegiance to and service for the one and true God.

Turning to the medieval phase, we have observed the emergence of diverse and competing approaches to the category of divine oneness, spurred by encounters with intellectual and spiritual traditions in Christianity and Islam, and Greek philosophy. Many of these approaches can be categorized into one of two overarching traditions: The philosophical tradition, which largely upholds the notion of divine simplicity, and its kabbalistic counterpart, which embraces the notion of divine complexity. Despite significant and multifaceted differences between them, both traditions share two crucial features: First, they revisit the premedieval understanding of God as a personality and tend to reinterpret it, to varying degrees, in causal terms (though notable exceptions include Baḥya ibn Paquda and Judah Halevi); second, they assert that their distinct conception of divinity and its oneness is encoded within the Hebrew Bible as part of its hidden and deeper meaning, which can only be revealed through esoteric exegesis. In either case, traditional concepts of divine oneness undergo reconfiguration through respective lenses.

Regarding the modern phase, its Jewish landscape is characterized by a broad spectrum of epistemic and normative orientations. With immanent concepts of reality dominating, the category of a transcendent deity is deemed an “unnecessary hypothesis” for addressing many aspects of human life. Additionally, any concepts of God that are empirically untenable or morally problematic undergo major revision or are outright abandoned. Furthermore, any self-conscious Jews who have internalized the contemporary ethos of diversity and pluralism feel compelled to revisit how their tradition can recognize the validity of other faiths and value systems. These developments have given rise to a wide range of Jewish perspectives on the category of divinity and its oneness. I have elucidated these and other points through two pairs of contrastive thinkers: Freud vs. Frankl, Kaplan vs. Heschel.

Paths Not Taken

Readers may have noticed that throughout, I have deliberately refrained from using a particular word, one highly relevant to our discussion – namely, “monotheism” (except where it appears in quotations). Its use in English can be traced back as far as to Henry More in the seventeenth century. However, I find that its application often complicates rather than clarifies the inquiry, as its meaning can vary significantly depending on the context and individual interpretation. In other words, there is a tendency to regard as “monotheism” the religion of those who claim to be “monotheistic,” and then readjust the semantic range of the term to fit the case at hand. I refrain from providing a rigid normative definition of the term because, viewed from the history of ideas, there is no single “true” meaning that reigns supreme. Instead, I aim to present various prominent Jewish perspectives on divine oneness, which – however varying and contradictory they may be – can all rightfully be described as “monotheistic.”

Space limitations have made it necessary to omit other influential thinkers and important topics. For example, I myself initially contemplated contrasting two modern Orthodox Zionist thinkers, Abraham Yitzhak ha-Cohen Kook (1865–1935) and Yeshayahu Leibowitz (1903–1994). Kook advocated for an all-encompassing panentheistic outlook of divine oneness through Kabbalistic-Hegelian dialectics, identifying messianic sparks in secular Zionism (Ravitzky 1996; Mirsky 2016). Conversely, Leibowitz, with his idiosyncratic Maimonidean-Kantian convictions, sought to purify religion from any human cause or interest, including Zionism, and was acutely vigilant against any risk of the State of Israel committing political idolatry in its own name (Leibowitz 1995; Sagi 2016). Another significant area is modern Jewish feminism. A variety of Jewish feminisms have called for reevaluation of traditional concepts and communal conventions, leading to invaluable changes in women’s status in Jewish life and a flourishing of feminist scholarship and theology (Tirosh-Samuelson 2012; Irshai 2022). However, regarding the category of divine oneness, I find it premature to address feminist treatments at this stage. This is because conceptions in the feminist discourse are not yet drastically unique but rather variants of existing ones, mostly asexual or bisexual, and I anticipate witnessing the emerging of much more radical and creative accounts in that discourse at any moment. Overall, the purpose of this Element, as previously stated, is not to provide a comprehensive discussion of God’s oneness in the Jewish tradition, but to present a selective, typological overview, fostering meta-reflection on its complexity, profundity, and internal diversity.

The Problem of Truth

As a closure, I would like to comment on the existential and normative significance of embracing the legitimacy of diverse perspectives on divine oneness – put differently, of setting aside one’s own predilections, at least temporarily, and understanding why adherents of each viewpoint find theirs most convincing.

Human plurality is not merely a fact of life but a fundamental aspect of our humanness, and therefore any attempt to eliminate this diversity risks leading us toward genocidal attitudes. In this regard, religions have often been criticized for fueling discord and conflict within the human family. While it is true that religions have provided invaluable benefits to countless people throughout history, some religions have also promoted intolerance, prejudice, and violence toward other paths, whether religious or otherwise. In my view, these perceived maladies stem from the inherent nature of religious conviction, which can absolutize itself as sacrosanct, thereby giving rise to three pathological tendencies in its adherents:

1. (1) A tendency to entrench themselves in their own convictions, to the extent that they disregard or rationalize away any fact or view that could challenge their beliefs, and furthermore, they may even celebrate such apologetic dismissal (problem of dogmatism and confirmation bias; cf. Haidt 2012).

2. (2) A tendency to perceive anyone holding a different or opposing view not only as incorrect but also as evil (problem of demonization; cf. Keen 1992).

3. (3) A tendency to hold their convictions so fervently that they may justify committing acts they would otherwise consider morally reprehensible, all in the name of their ideals (problem of altruistic violence; Dalai Lama 2010: esp., 145–161; Sacks 2015).

Some critics attribute these tendencies not to the general category of religion but rather to a specific type, namely, “monotheistic” faiths. It is undeniable that – unlike polytheistic religions which acknowledge a multitude of gods and thus a variety of valid religious practices and lifestyles – belief in a single, absolute God has often been associated with proclaiming one exclusive truth and one exclusive path of worship and life. It is no surprise then that many crusades, jihads, and other religious conflicts have arisen from and been justified by such exclusive convictions. That being said, I concur with the view that the nexus between these tendencies and “monotheistic” traditions is not inevitable – that the belief in a single, transcendent God can actually foster an appreciation of divergence and plurality. In other words, if adherents acknowledge that the reality of transcendence, qua transcendence, cannot be confined to a single form of worship and lifestyle, they can embrace – and even admire – the outlooks of other faith traditions without compromising their own beliefs (Hagami 1986; Chouraqui 2000, 2013; Halbertal 2007). The fact that many devout “monotheists” embody virtues of generosity and openness to people outside of their own faith traditions also suggests that we should turn elsewhere to find the source of the aforementioned pathologies.

In my view, the root cause of those pathologies lies neither in religion nor in “monotheistic” faith, but rather in absolutism – the conviction of being right, of possessing the absolute truth, whether religious or not (or if you prefer, we can call it “conviction about conviction”). Once consumed by this unwavering sense of self-certainty, people readily regard their own convictions – whether racial, national, political, historical, ethical, scientific, aesthetic, or religious – as absolute and nonnegotiable. Consequently, they risk denying the humanness of anyone who holds a differing viewpoint, potentially leading to ideologically inspired violence, whether physical or otherwise. In this regard, religious intolerance is not necessarily the cause of absolutism but rather can be a consequence thereof. Put differently, any form of absolutism is likely to adopt the characteristics of religious dogmatism, as its adherents view themselves – and the reasoning or normative intuition that underlies their conviction – as infallible and God-like. It is no surprise, then, that the political absolutism seen in modern secular states, whether totalitarian or despotic, often exhibits dogmatic tendencies reminiscent of premodern religious persecutions. I also ponder the violence perpetrated by religious extremists in the name of their religion – how much of it originates primarily from the fact of their being religious rather than from their conviction of being right. Be that as it may, Michael Faraday’s oft-quoted aphorism, whether intended or not, aptly captures the peril at hand: “There’s nothing quite as frightening as someone who knows they are right” – or more precisely, someone who believes they know they are right.

And here lies the crucial significance of nurturing genuine appreciation for diverse approaches to divine oneness. True, it is frequently argued that one should not, and indeed cannot, accept the legitimacy of such divergent and seemingly contradictory claims, as doing so defies logic (read: human logic). This contention, however, strikes me as misguided for several reasons. First, it treats logical truth as a single concept defining truth and the nature of reality, when in fact logical truth is just one aspect of reality and may not even be primary to human reality (Nagel 2012). Second, it overlooks the fundamental, pluralistic, and multifaceted nature of humanity, attempting to force a human phenomenon into a monolithic (and therefore inhuman) framework (Nakamura 1993). And, thirdly, it relies on the Aristotelian logic of “noncontradiction,” which is itself indemonstrable; for its logical demonstration necessitates the application of the same principle, resulting in infinite regress (Priest 2006). It should be clear that I do not hereby intend to dismiss the classical category of logic, but rather to address its limitations – or, in other words, to expand the category of logic so that it can accommodate other forms of logic, such as the polyphonic, the dialethic, and the meta-rational.

In this regard, Judaism – much like other non-Western traditions such as Hinduism and Buddhism – exhibits a distinct heuristic inclination that promotes multifaceted modes of thinking, exploring the categories of reality, humanity, and divinity from multidimensional, paraconsistent perspectives. A prime example is the rabbinic maxim, “these and those are the words of the living God” (BT Eruvin 14b), suggesting that divine truth is vast enough to encompass varying human understandings of it, and thus each perspective should be accepted – in fact revered – as potentially manifesting that truth (Levin 2016: vii, 97–113; Sagi 2007). Some Jewish thinkers even hold a dialogical notion of truth, viewing truth as emerging through the encounter between different viewpoints; therefore, exposure to divergent outlooks is seen as essential for enriching one’s own life (for dialogical concepts of truth in Judaism, cf. Halbertal 1997: 63–67; Sagi 2007: 20–22). This all implies that holding multiple and seemingly contradictory perspectives does not equate to compromise; instead, it can signify excellence in both intellectual and religious terms.

Admittedly, there are instances of Jewish figures past and present dismissing opinions other than their own as erroneous or heretical. Nonetheless, such foundational texts of Judaism as the Mishna, the Talmud, the Zohar, and the Mikraot Gedolot (“Great Scriptures,” also known as the “Rabbinic Bible”) are all polyphonic in nature, presenting divergent opinions on Jewish teachings without necessarily endorsing any single one. Notably, Jewish humor and folklore often reflect such modes of thinking. An anecdote tells of a rabbi settling a dispute between two neighbors, with his attendant questioning: “But, rebbe, what do you mean, ‘This one is right,’ and ‘That one is also right’? They can’t both be right!” The rabbi, after a moment’s thought, replied, “You know, you’re also right.”

Overall, studying these and other Jewish sources – that is, learning to appreciate their inherent plurality of perspectives – can potentially liberate ourselves and others from our own presupposed convictions. (Here I add “can” advisedly because others may be inclined to study those sources in order to choose or develop a perspective that aligns best with their preconceived convictions, while dismissing all nonconforming viewpoints.)

Ultimately, the concept of truth that guides our lives inevitably shapes how we engage with individuals whose perspectives differ from our own. Some may perceive the mere presence of such individuals as threatening because their views have the potential to challenge our deeply held convictions, which constitute the bedrock of our values and selfhood. Nevertheless, genuine human interaction, as well as any honest attempt of learning, require a willingness to remain open to and be transformed by whatever we encounter. In this light, earnest exploration of diverse and divergent opinions on the present (or any) topic can potentially foster flexible, multifaceted modes of thinking that allow us to embrace the rich diversity of humanity. If this is the case, then isn’t the inquiry of this kind relevant to the well-being of our humanness, especially at a time when human society increasingly plagued by divisiveness, fragmentation, and intolerance?

Finally, a message to religious believers: If the reality of the divine is real, embracing the plurality at hand can also free something else from the constraints of our own convictions – namely, the reality of God itself. Therefore, I invite you to reflect on the following seemingly straightforward yet profound words of Franz Rosenzweig: “The chief thing is not whether a person ‘believes’ in the good Lord; what matters is that the person opens all the five senses and sees the facts – at the risk that even the good Lord may be found among them” (from a letter to his mother, dated August 15, 1921; cf. Glazer 1999: 25).

I am asleep but my heart is awake.

Hark, my Beloved knocks!

“Open for Me”

Song of Songs 5:2