Entertaining the Trinity Unawares: Genesis xviii in Western Christian Interpretation

Abstract

Abraham's encounter at Mamre (Genesis xviii.1–16) captivated the Christian imagination from the tradition's very origins. The story hints at God's self-disclosure in a triad of visitors – a theophany that evoked the presence of the Logos or even the Trinity. This article examines late antique exegetical trajectories, focusing upon the interaction between text and expositor in light of the latter's socio-historical context. For patristic exegetes, the Mamre account contained profound spiritual truth if read through the correct doctrinal lens, while presenting a foothold for heresy to the unwary. Changing visions of Trinitarian orthodoxy thus gave rise to new strategies of reading.

JECS

Journal of Early Christian Studies

ThLZ

Theologische Literaturzeitung

ZNTW

Zeitschrift für Neutestamentliche Wissenschaft

Andrej Rublev's painting known as the ‘Hospitality of Abraham’, but more frequently referred to as the ‘Old Testament Trinity’, is amongst the best known and most admired of Russian icons.¹ The fifteenth-century work depicts three seated, winged figures, inclining towards one another around a table against the background of trees and a building. The three figures are colourfully attired, of apparently equal size, and do not display any obvious signs of rank or hierarchy. As its title suggests, the icon depicts the appearance of three strangers to the Israelite patriarch Abraham and his wife Sarah at the oaks of Mamre, as recounted in the Hebrew Scriptures. According to Genesis xviii, Abraham welcomes the three visitors with great deference, washing their feet and preparing a lavish meal for them.² Abraham's hospitality is rewarded with the promise of the imminent birth of his and Sarah's son, Isaac. After the meal, the men depart, looking towards Sodom, while ‘the Lord’ (; κυϱίoς [LXX]; dominus [Vulgate]) remains behind to speak with Abraham about the city's imminent destruction.

The primary cause of the story's enduring fascination for Christian expositors, however, hinges less on the events narrated and more on the nature of Abraham's visitors, particularly in as much as the text makes it clear that it is God who speaks through them, first by questioning Abraham about Sarah's laughter, and later by revealing to Abraham Sodom's impending punishment. Abraham's visit thus not only qualifies as a theophany – itself a rare occurrence in the Hebrew Scriptures – but further raises the intriguing spectre of the one God's self-disclosure in the triad of visitors.

As the better-known title of Rublev's icon suggests, Christians for much of history have readily identified Genesis xviii as a revelation of the Holy Trinity. From the perspective of late antique interpreters, however, identifying Abraham's visitors with the three persons of the Godhead was anything but obvious. Even to suggest that the divinity had been in some form present at Mamre raised serious questions: might not Abraham's conversation with the Lord have taken place before the arrival and after the departure of the three? If Abraham addressed only one as Lord, was this evidence that two of the three were of lesser rank? Furthermore, in what sense could the first person of the Trinity be said to appear in physical form, not to mention partake of such human activities as eating or having his feet washed? Or, if it was not the Father but the Son whom one recognised in the encounter, what did it mean to posit human form of Christ prior to the incarnation?

Early Christian interpreters of Genesis xviii struggled with all these questions, as well as their implications for theological discourse; indeed, from the middle of the second through the beginning of the sixth century, the identity of Abraham's mysterious visitors provided a flashpoint for Christological and, by extension, Trinitarian disputes.³ For historians of late antiquity, different writers’ exegetical identification of Abraham's visitors accordingly provides a measure by which to assess the development of Trinitarian thought in this era. In other words, the more securely entrenched ideas of God's triune nature were within a particular theological context, the more readily exegetes read Genesis xviii as a pre-incarnational Trinitarian manifestation. This connection – while both demonstrable and intuitively appealing – did not, of course, hold true in all cases: some writers remained committed to historical readings of the passage that had fallen out of step with prevailing notions of orthodoxy, while others speculatively and perhaps presciently explored the text's surplus of meaning in ways that would become congenial to the Christian tradition's understanding only centuries later.

This article examines the development of two exegetical trajectories that sought to appropriate Genesis xviii for late antique understandings of the Trinity. First a ‘Logos-centric’ reading of the text will be traced. According to this Abraham encountered the pre-incarnate Christ and two accompanying angels. This reading was initially proposed by Justin Martyr and remained influential for centuries, until it proved too great a liability for proponents of Nicene consubstantiality between Father and Son in the late fourth century. Augustine's contributions to and critiques of this model will then be discussed. While remnants of Justin's exegesis remain palpably influential, exegetes at the beginning of the fifth century began to cast about for new readings of Genesis xviii that could be deployed in the service of changing Trinitarian doctrine. In this process, Western writers benefited from the work of one of their Greek predecessors, namely Origen of Alexandria. Finally, the impact of an alternative trajectory of interpretation that would come to replace Justin's Logos-centric exegesis will be considered, tracing its development from mere Trinitarian premonitions in Origen's own writings to a full-fledged Trinitarian reading of Genesis xviii in the work of sixth-century exegetes like Caesarius of Arles.

Justin and Hilary: the Logos at Mamre

Little is known about Justin Martyr's life aside from the rhetorically stylised and thus suspect biographical data contained in his own writings. The Dialogue with Trypho, one of Justin's three unquestionably authentic works, is therefore difficult to date with greater precision than to the first half of the second century. Like Justin's other writings, the Dialogue is an apology for the Christian faith; unlike the First and Second apologies, however, it is set in the narrative framework of a philosophical encounter between Justin and Trypho, a Jew. In the course of their prolonged conversation – primarily an opportunity for Justin to instruct his reader alongside Trypho – Justin attempts to show that Christianity is the new law, applicable to all (chs 10–31); that Scripture shows Jesus to be the Christ (chs 31–108); and finally, that Christians, not Jews, are the true people of God (chs 109–42).⁴

Throughout the book, Justin is obviously concerned to refute the charge that Christians do not keep the law and therefore cannot be heirs to the Scriptures and traditions of the Jewish people. Abraham, in light of his pre-Mosaic and thus uncircumcised existence, becomes an important ally in this process;⁵ Justin references him over a hundred times in the Dialogue.⁶ His discussion of the Mamre encounter takes up part of chapter 56. Genesis xviii and xix – the accounts of Abraham's encounter at Mamre and of Lot's visit at Sodom – form a logical and literary unit for him: two of Abraham's three visitors are thus dispatched to Sodom, while the third remains behind to speak with Abraham and Sarah.⁷ Justin can draw on data from Genesis xix to establish his argument that a second divine entity exists, ‘distinct from God the Creator; in number, I mean, but not [distinct] in mind’.⁸ At Sodom, Scripture reports that ‘the Lord rained on Sodom and Gomorrah sulfur and fire from the Lord out of heaven’ (Genesis xix.24, NRSV). The duality of Lordship implied by the passage, one raining sulfur and fire, one the originator of those elements, reflects the existence of two gods, Justin argues. One of these, the Father and Maker of all things, remains in heaven, invisible and thus inaccessible to creation.⁹ The other, identified by Justin as Son and Logos, ministers to the Father in all things as his earthly representative.

Logically then, Justin argues, any person who, according to Scripture, met with or spoke to God, encountered Christ. No theophany is possible without the mediation of the Logos: ‘Thus, neither Abraham, nor Isaac, nor Jacob, nor any other man saw the Father and ineffable Lord of all creatures and of God himself, but [they saw] him who, according to God's will, is God the Son, and his angel because of his serving the Father's will.’¹⁰ Having thus established to the satisfaction of his rhetorical audience the distinction between two gods, one heavenly and remote, the other serving as that deity's earthly mediator, Justin can argue that the God encountered by Abraham in Genesis xviii is perforce the Logos. He has appeared to Abraham in the guise of an angel (ἄγγελος) – an appropriate title, Justin argues, in light of the Son's work as messenger on behalf of the Father.¹¹ His divine identity is nevertheless established by a subsequent encounter: God, having announced Sarah's pregnancy, later returns to promise Abraham the continuation of his lineage through Isaac (Genesis xxi.9–12). The identity of messages, Justin suggests, points to the identity of the messengers.¹²

Abraham's other two visitors are lesser angelic beings, Justin argues, and are sent to serve and assist the Logos in carrying out His task. Accordingly, they go ahead to Sodom to reveal God's plan to Lot and his family while the Son remains behind to converse with Abraham. Thereafter, Justin hypothesises, the Logos rejoins the angels in order to speak with Lot directly: ‘And when he came [to Sodom], the two angels no longer conversed with Lot, but Himself, as the Scripture makes evident.’¹³ The Logos, for Justin, is superior to angels in wisdom and authority; he shares the Father's prophetic insight and communicates it to human beings. While numerically distinct from the Father to the point that Justin can freely speak of the existence of two gods, the Logos nevertheless shares the Father's will so completely ‘that He has never at any time done anything which He who made the world – above whom there is no other God – has not wished Him both to do and to engage Himself with’.¹⁴ Justin nevertheless emphasises the relative, if only implicit, authority that the Father exercises over the Son: the latter acts only upon the Father's direction and, like creation, recognises the Father as Lord.¹⁵ The Christology that emerges from a close reading of the Dialogue's treatment of Genesis xviii, as well as Justin's work more generally, is thus tinged with what might anachronistically be called subordinationism – the presupposition that Christ, while divine and superior to creation, is nevertheless subordinated to the Father.

Such subordinationism did not, of course, pose any difficulties for Christian orthodoxy in Justin's era; indeed, the emphasis on the Father's insuperable power and divinity was clearly conducive to Christian/Jewish dialogue, whether real or rhetorical. Nearly two hundred years after Justin's death, however, the theological landscape had changed dramatically: the ‘Homoian controversy’ had pitted those who supported a subordinationist Christology as faithful to both Scripture and tradition against those who argued for essential equality between the first and second persons of the Trinity.¹⁶ One of the most vocal champions of Nicene orthodoxy was Hilary, bishop of Poitiers, whose imperially-ordered exile from his see catalysed his sustained and energetic service to the pro-Nicene cause.¹⁷

Central among Hilary's literary effects from this era is his treatise On the Trinity, a lengthy polemic against ‘certain individuals who so distort the mystery of the evangelical faith that they deny the birth of the only-begotten God, while piously professing that there is only one God’.¹⁸ This ambitious work encompasses twelve books, the first three of which appear to have been written some time before the rest of the work.¹⁹ In book iv, Hilary sets out to address ‘certain facts … in the following Books that the knowledge of the truth may become clearer after we have pointed out all their fallacies and blasphemous doctrines’ (iv.1, p. 91). Hilary thus initially establishes the parameters of Homoian Christianity's exegetical vision for his audience. He lists, first, a number of scriptural passages significant for the Homoian Christian enterprise (iv.8), before citing the Epistle of Arius to Alexander (iv.12–13) – a kind of proto-Homoian creed – in its entirety. This is the reading of Scripture that Hilary seeks to supplant with his own, pro-Nicene exegesis, which, Hilary argues, is more faithful both to the meaning of the text and also to the tradition of the Fathers.

In light of the significance of Old Testament proof-texts for the Homoian cause, Hilary begins by countering ‘the explanation of their faith, or, rather, of their perfidy, which these blasphemous men give; namely, that Moses taught that there is only one God’.²⁰ Having established divine partnership in the creation of the world, Hilary moves on to consider the Abrahamic theophanies, beginning with the Angel of the Lord's discourse with Hagar (Genesis xvi.4.23–4). Abraham's encounter at Mamre, and Lot's visit at Sodom occupy paragraphs 25 through 29 of the book. Hilary's exegesis here holds few surprises for readers of Justin's Dialogue: Hilary urges his readers to assume continuity between the promise of Isaac's birth and progeny in Genesis xvii and xviii, and as the fulfillment of said promise in Genesis xxi. If, as Scripture testifies, the initial promise was made through God and its fulfilment brought about by God, Hilary argues, must the reader not assume that the reiteration of the promise at Mamre was accomplished through God as well – even if that God was also rightly called ‘Man’ (‘vir’)?:

Compare the accounts! The man indeed will come for this purpose, that Sara may conceive and give birth. Learn about the fulfillment! The Lord and God came, therefore that Sara might conceive and give birth. The man spoke with the power of God, but it was God who performed the work of God. Thus, by word and action, He indicates that He is God. (iv.27, p. 116)

That this ‘Man’ is not only ‘Lord’ (‘dominus’) but also ‘Judge’ (‘iudex’) is revealed by the events of Genesis xix: while God, that is to say the Logos, lingers with Abraham, the two accompanying angels proceed to Sodom.²¹ Only at the conclusion of the conversation with Abraham does God execute judgement on the city: ‘“The Lord poured down sulphur and fire from the Lord”’ (iv.29, pp. 117–18). The shared name like the shared power, Hilary points out, indicates the shared nature between Father and Son. They can nevertheless be differentiated by virtue of their respective offices and their relationship to one another: ‘Hence, the Lord gave what the Lord had received from the Lord’ (iv.29, p. 118).

Hilary's appropriation of Justin is in many regards a logical step. Practically speaking, Justin's exegesis of Genesis xviii seems to have set the tone for subsequent generations of interpreters; as has been noted already, a Logos-centric reading is well-attested in the West as well as in the Greek and Syriac East.²² The rhetorical aims of Justin and Hilary furthermore share a number of commonalities, despite their works being separated by two centuries. On their most basic level, both Justin's Dialogus and Hilary's De Trinitate represent endeavours to construct Christianity as a religion that is not only divinely revealed, but also historically grounded and logically consistent. To define Christian orthodoxy depended, however, on first establishing what had to be excluded from that definition. In the process, both Justin and Hilary assumed the task of demarcating boundaries between competing groups and drawing lines between otherwise dangerously fluid social realities. In other words, in order to educate their audiences about what counted as truly Christian, both writers had to name, establish and ultimately reject its viable alternatives, whether Judaism or heterodox Christianity. Both the Dialogue and the De Trinitate moreover share a central concern for demonstrating Christ's divinity. Both texts are thus designed to counter Jewish or Homoian emphases upon upholding the singularity – in Hilary's words: the solitude (solitudo) – of the Father. Indeed, polemical texts during the fourth and fifth centuries consciously exploited this perceived family resemblance between Jews and Homoians by accusing Christians holding to subordinationist Christologies of ‘Jewishness’.²³

Such similarities between Justin's and Hilary's respective agendas do not, however, mask the theological disconnect wrought by two hundred years of doctrinal development. For Justin, establishing Christianity thus depended upon persuading his dialogue partner – and, more proximately, his readers – that Scripture testified to the shared name as well as to the unity of wills between Father and Son. By Hilary's era, however, Homoian Christians were happy to concede both points while disputing nevertheless that the Logos shared the Father's divine essence. Justin's apparent willingness to subordinate the Son to the Father thus threatened to open the floodgates for Homoian adoption of the Dialogue's exegesis of Genesis xviii. Worse still, Homoians might claim Justin as sharing their theological commitments, attesting to Homoian Christianity's superior historical pedigree – and indeed they might have been entirely justified in doing so.

Hilary sought to circumvent such appropriation of Justin's reading by emphasising the unity of power – as well as of name and will – between Father and Son in these chapters. By the first decade of the fifth century, however, Hilary's adaptation of Justin's exegesis had apparently failed to hold up against Homoian appropriation. Hilary's younger contemporary and fellow pro-Nicene Augustine of Hippo thus wrote that, concerning the exposition of Genesis xviii as involving the Logos and two angels, ‘If only one man, you see, had appeared to Abraham, the people who maintain that the Son was visible in his own proper substance even before he was born of the virgin would surely have been very quick to claim that this was he. Only the Father, they say, is referred to by the words “To the invisible and only God (Phil. ii.7).”’²⁴ To find the Logos – and only the Logos – amongst Abraham's visitors was, by Augustine's time, the prerogative of those for whom the Son's essence differed from the Father's. In light of the changing theological landscape and lingering Trinitarian concerns, Augustine apparently felt compelled to cast about for alternative readings to bring the interpretation of these key texts into line with contemporary notions of pro-Nicene orthodoxy.

Augustine of Hippo: Trinitarian suspicions

Augustine's rich and well-preserved body of work unsurprisingly includes numerous texts that draw upon Genesis xviii and xix. Many of these instances are, however, either unhelpful or downright misleading when it comes to divining Augustine's Trinitarian understanding of the passage. Augustine, for example, uses these chapters to gain insight into the nature of angelic bodies and, by extension, the bodies that Christians could expect to enjoy after the resurrection,²⁵ or to support his claim that good as well as evil angels contribute to the overthrow of cities.²⁶ By contrast, Augustine exploits the Trinitarian or Christological implications of the passage in three works, all of which belong to his mature theological thought: De civitate Dei, Sermo vii, and, at greater length than in either of the other two, De Trinitate.²⁷ True to their respective genres and doctrinal foci, each work emphasises different aspects of Augustine's reading; they nevertheless present a coherent picture marked perhaps more strongly by its departure from Augustine's predecessors than by its development of exegetical alternatives.

Augustine's audience is made aware immediately that Justin's and Hilary's readings of Genesis xviii continue to enjoy widespread familiarity and support. Each sustained treatment of Abraham's encounter at Mamre thus begins with Augustine's polemic against those ‘people who maintain that the Son was visible in his own proper substance even before he was born of the virgin’.²⁸ Indeed, Augustine's contemporaries appear eager to discover Christ in a variety of passages from the Hebrew Scriptures: Augustine also complains about those who understand as Christ the Angel of the Lord who prevents Abraham from sacrificing Isaac, and intimates that in passages like Genesis xviii, the plurality of visitors was expressly designed to prevent Christians from mistakenly identifying one of them as the pre-incarnate Christ.²⁹

Yet while Augustine rejects Justin's and Hilary's argument that Abraham entertained the Logos at Mamre as problematic to orthodox Christology, he nevertheless retains aspects of his predecessors’ readings. Chief amongst these is the continuity that Augustine envisions between Genesis xviii and xix and, by extension, between Abraham's and Lot's visitors. Augustine expressly rejects the notion, championed by Hilary, that the Lord remained behind at Mamre, sending his two angelic companions ahead to Sodom; to argue thus threatens to ‘divide the trinity up and make it a duality’.³⁰ He nevertheless emphasises that the way in which Lot encounters God in Sodom corresponds to the theophany experienced by Abraham at Mamre. In both cases Augustine thus confidently identifies the visitors as angels, an assessment that he shares with Justin and Hilary.³¹ Unlike his predecessors, however, he must labour against those who prefer an overly literal reading, suggesting that Abraham only encountered ‘men’, since his rejection of Hilary's Logos hypothesis effectively fractures the continuity between the two chapters: if the positive identification of Lot's visitors in Genesis xix as angelic cannot be retrojected into Genesis xviii, Augustine has to find other sources outside the wording of Scripture to substantiate his claim.

Part of the answer for Augustine rests upon his use of Hebrews xiii.2 and its exhortation to extend hospitality to strangers ‘for by doing that some have entertained angels without knowing it’, as an intertext for Genesis xviii. By and large, however, Augustine seems reluctant to arbitrate between the different scriptural identifications of Abraham's visitors, favouring a plenary reading.³² While Abraham's visitors rightly can be said to be both men and angels, to claim that they were only men is unacceptable: ‘[c]annot people of this opinion [that the men at Mamre were only men] see what difficulties those three men make for them who appeared to Abraham, with the introductory remark, “The Lord appeared to him”?’³³

It is at the point where Augustine turns to examining the exegetical crux of the text – the challenge of reconciling the interaction of Abraham and Lot with a plurality of ‘men’ or ‘angels’ with their address of the one God – that subtle differences in interpretive emphasis between Augustine's treatment of Genesis xviii in De Trinitate and in De civitate Dei become apparent.³⁴ While his reading in City of God is likely to be chronologically the later, it appears to be logically prior to that offered in De Trinitate. There, Augustine emphasises the patriarchs’ ability to recognise God in the visitors, their human or angelic attributes notwithstanding:

It is thus far more credible that both Abraham in the three and Lot in the two men recognized the Lord, addressing Him in the singular number, even when those they addressed were [several] persons; for they received them as they did for no other reason than that they might minister human food to them as men who were in need. Yet there was about them something so excellent, that those who showed them hospitality as men could not doubt that God was in them as He had been in the prophets, and therefore they sometimes addressed them in the plural, and sometimes God in them in the singular.³⁵

These theophanies were not, of course, manifestations of God in his proper substance, Augustine argues; rather, God, without undergoing any kind of change, made use of created matter subject to him to manifest himself to his people.³⁶ Augustine reiterates this distinction between the impossibility of ‘seeing’ God in his plenitude and the patriarchs’ experience of God ‘appearing’ to them in his treatise on seeing God: the mode of divine revelation is thus chosen by God's will as, for example, in the case of the Holy Spirit's appearance as a dove at Christ's baptism, rather than arising from the nature of the Trinity.³⁷ Proving themselves worthy of the revelation, Abraham, Lot and others ‘recognized the Lord in the angels, perceived the inhabitants in the habitation, gave glory to the one seated on the throne, not to those who carried it’.³⁸

De Trinitate, while implicitly assenting to Augustine's argument in City of God, focuses less upon how God is present in the patriarchs’ visitors and more upon what their multiplicity expresses about God's nature. The presence of three men at Mamre – none of whom are said ‘to have been superior to the others in stature or age or authority’ – encourages Augustine to ask: ‘[W]hy may we not take the episode as a visible intimation by means of visible creations of the equality of the triad, and of the single identity of substance in the three persons?’³⁹ While the three guests are thus in their own substance either men or angels, they also serve both as mouthpieces of divine communication and as symbolic expressions of the divine nature. Augustine makes the latter point most strongly in Sermo vii, where he asks rhetorically: ‘Why three? Can it have been the Trinity itself? Then why “Lord” in the singular? Because the Trinity is one Lord not three Lords, and the Trinity is one God, not three Gods; one substance, three persons.’⁴⁰ Indeed, Augustine argues, even where God manifested Himself in only two angels, the same principle of singular divinity revealed in a plurality of persons applies. In Lot's visitors Augustine thus discerns the symbolic representation of Christ and the Holy Spirit – the two persons of the Trinity said to be ‘sent’.⁴¹

Augustine is frequently acknowledged as one of the greatest expositors – indeed, perhaps the greatest expositor – of the Trinity in pre-modern times. In light of his theological perspicacity, Augustine's ability to discern the problematic nature of prior interpretations of Genesis xviii does not come as a surprise to the reader. If the reality and particularity of the incarnation are to be preserved, the appearance of the Logos in human form in the Hebrew Scriptures becomes suspect. The increasing appreciation of the shared essence of Father and Son over the course of the fourth century made obsolete the vision of Christ as God's messenger championed by Justin and, in modified form, Hilary. The transition from seeing the Logos at Mamre to Augustine's more Trinitarian vision was nevertheless neither smooth nor easy: Augustine manifestly struggled to dislodge the prior reading in the minds of his audience, while at the same time grappling with the at times baffling complexities of the text.

Intriguingly, Augustine's reading of Genesis xviii does not appear to draw upon the exegetical work of his mentor, Ambrose of Milan.⁴² In part, Augustine's reluctance may reflect neglect rather than rejection: while Genesis xviii appears several times in Ambrose's writings, the bishop nowhere explores the text's full interpretive potential. Even in his De Abraham, Ambrose's extensive discussion of Abraham's life as exemplary for catechumens, the patriarch's encounter with the three visitors is mined primarily for moral rather than doctrinal instruction.⁴³ Ambrose nevertheless surprises readers familiar with the interpretation of his older contemporary, Hilary, by offering an almost off-handed Trinitarian reading of the passage. At the appearance of the three in Genesis xviii.2, Ambrose thus notes: ‘God appeared to him, and he saw Three. He for whom God shines sees the Trinity. He does not recognise the Father without the Son, nor does he confess the Son without the Holy Spirit.’⁴⁴ Similarly, Ambrose reads the ‘three measures of a single flour’ with which Sarah prepares a feast for the visitors as referring to the Church's ‘affirming the Trinity of the Godhead, worshipping Father, Son, and Holy Spirit in equal measures and with reverence, and distinguishing Them by the persons’ own proper attributes’.⁴⁵

Given Ambrose's reputation as a thoughtful but not broadly innovative theologian, his confident reading of Genesis xviii as expressive of the mystery of the Trinity is perhaps surprising in the context of other, more conservative Western Christian interpretations of the passage.⁴⁶ However, the influence that Eastern writers had upon Ambrose's theological development is impossible to discount. Ambrose's ability to read Greek, rare amongst the Western Fathers, thus allowed him access to the writings of Origen of Alexandria. The latter's interpretation of Genesis xviii unlocked alternative avenues of Trinitarian interpretation. Indeed, as the work of Caesarius of Arles attests, Origen's influence extended even beyond Ambrose's era and into the sixth century. While, by the late fourth century, exegesis of Genesis xviii by Justin and Hilary had reached a dead end, and Augustine's tentative proposal of an alternative reading threatened to lose itself in correcting the errors of his predecessors, Origen's analysis became central to forging an understanding of the Trinity at Mamre that continues to assert itself to the present day.

Origen and Caesarius: from Trinitarian premonitions to consensus

Writing on the eve of the the Decian persecution, Origen formulated much of his exegesis and theology defensively, by addressing perceived threats to the incipient Christian orthodoxy of his era. He thus developed his understanding of the Trinity originally as a rejection of the so-called Sabellian heresy, according to which Father, Son and Holy Spirit were simply different names for the same divine entity.⁴⁷ By the end of the fourth century, well over a century after Origen's death, Sabellianism appeared, if indeed it appeared at all, only in the genealogies of the heresies du jour. The continued relevance of Origen's exegesis to Trinitarian readings of later centuries attests to Origen's superb interpretive instincts, helped along by a homiletical culture that increasingly relied upon recycling the sermons of famous preachers from bygone eras.⁴⁸ Origen's homilies on the Old Testament, thanks in part to their translation into Latin by Rufinus and their impact upon Ambrose, thus insinuated themselves into the homiletic oeuvre of fifth- and sixth-century theologians.⁴⁹

Genesis xviii makes an appearance in the fourth of Origen's In Genesim homiliae, entitled ‘On that which is written: “God appeared to Abraham”’. Therein, Origen, for the first time since Justin Martyr some sixty years prior, considers the relevance of Abraham's visitors to the Christians of his era.⁵⁰ Origen's indebtedness to Justin's reading of the threesome at Mamre as representing Christ and two angelic companions quickly becomes apparent. He thus affirms that in Abraham's case, ‘the Lord also was present with Abraham with two angels, but two angels alone proceed to Lot’.⁵¹ As a result, Origen argues, Abraham, unlike Lot, received not only those powers able to destroy but also him who is capable of salvation.

Origen's attention to the details of the text, spurred by his quest to discern ‘what [a verse of Scripture] does to help me who have come to hear what the Holy Spirit teaches the human race’, however, encourages him to venture into alternative interpretive dimensions as well. When reflecting upon the three measures of flour, Origen thus remarks that ‘[Abraham] receives three men, he mixed the bread “with three measures of fine wheat flour”. Everything he does is mystical, everything is filled with mystery.’⁵² To this mystery Origen returns in the closing lines of his homily when he exhorts his congregation to live lives ‘worthy of knowledge of God, … that we, known by the Trinity, might also deserve to know the mystery of the Trinity fully, completely, and perfectly, the Lord Jesus Christ revealing it to us’.⁵³ Abraham's ability to know and be known by God – to both receive revelation and to discern the mystery revealed to him – are marks of his faith that Christians must emulate. To possess such insight implies an understanding of God's Triune nature. While Origen thus accepts without comment or exegetical justification that Abraham is visited by ‘the Lord and his angels’, the triadic appearance and corresponding preparation of ‘secret or hidden bread’ from three measures of flour manifestly point beyond the text's received interpretation towards a Trinitarian reading.⁵⁴

The potential inherent in Origen's interpretation of Genesis xviii was not lost on later readers. By Ambrose's era, the Church's teaching on the Trinity had expanded and gained shape well beyond its incipient state. Ambrose accordingly could develop the Trinitarian premonitions inherent in Origen's reading of the text with confidence: both his interpretation of the three measures of flour and his assertion that ‘[h]e for whom God shines bright sees the Trinity’ rely upon Origenist precedent.⁵⁵ Milan did not, however, become the final arena for Origen's hermeneutic. Caesarius of Arles, a sixth-century bishop in Roman Gaul, preached a sermon ‘On the three men who appeared to blessed Abraham’ that shows startling similarities to the fourth of Origen's Homiliae in Genesim while at the same time reflecting the fully developed Trinitarian understanding that Ambrose injected into his own reading of the text.⁵⁶

Caesarius’ understanding of the Trinity was shaped during his youth at the monastery of Lerins where he was first introduced to Ambrose's teaching and hymnody. Indeed, Carl Arnold has argued that a Hymnus ad Sextam attributed to Ambrose exerted lasting influence on Caesarius’ reading of Genesis xviii.⁵⁷ When Caesarius returns to the theme in his own Sermo lxxxiii, he thus inserts Ambrose's Trinitarian reading into the framework of Origen's homily.⁵⁸ Like Origen, Caesarius attributes the difference in the appearances to Abraham and Lot to their respective merit; Caesarius is, however, able to develop Origen's point further by suggesting that Lot, unlike Abraham, ‘received … only two, not the whole trinity’.⁵⁹ Like Origen, Caesarius emphasises the mystery inherent in the fact that Abraham ‘received the three men and served them loaves out of three measures’. Unlike Origen, however, Caesarius does not hesitate to spell out the full implications of these events: ‘Why is this, brethren, unless it means the mystery of the Trinity?’⁶⁰ Caesarius further follows Origen's etymological exposition of ‘Mamre’ as a place of ‘vision or discernment’, while nevertheless adding what that most felicitous vision that Abraham received was: ‘[T]he Father is God, the Son is God, the Holy Ghost is God, and these three are one God.’⁶¹

In short, aside from Origen's lengthy excursus into the role of women as exemplified by Sarah's behaviour, Caesarius adopts Origen's homily wholesale and in the process allows its potential for a Trinitarian exegesis of Genesis xviii to flower. Caesarius is not hampered by the need to define in precisely what fashion the Trinity subsisted in Abraham's three visitors, nor does he struggle with the weight of preceding eras’ ‘mistaken’ readings of the text. Nearly a century before Caesarius’ birth, the Council of Constantinople had supplemented the recently revived Nicene creed with an exposition of the Spirit's role and function, and had affirmed that the three divine hypostases shared ‘a single Godhead and power and substance, a dignity deserving the same honour and a co-eternal sovereignty’. Neither Constantinople nor its successors had settled the Trinitarian controversy beyond doubt or argument; they had, however, changed the field of vision of Western Christian exegetes. To see the Trinity in Abraham's visitors evidently came naturally to Caesarius and his audience – as indeed it still does for most Christians.

Contemporary biblical scholars, for obvious reasons, have sounded notes of caution against such a reading. Walter Brueggemann, for example, urges that ‘[t]here is no need … to seek a Christian statement of the Trinity [in Abraham's visitors]’,⁶² while Victor Hamilton, in recognition of the fact that older interpreters ‘seized upon the number three in v. 2 and identified them with the Trinity’, cautions that ‘such a statement reads a considerable amount into the text, and forces on the text an interpretation the text itself will not yield’.⁶³ Ancient Christian writers, of course, were not troubled by a desire to expound the Hebrew Scriptures in their socio-historical context, or motivated to avoid retrojecting their Christological insights into pre-Christian writings. Their aim was rather the thoroughgoing appropriation of Scripture for the faithful, confident that the same God who had been revealed in the New Testament had also sought to reveal Godself in the lives of the patriarchs and prophets.

Abraham at Mamre: between text and commentary

The poststructuralist historian Michel Foucault famously observed that ‘the commentary must say for the first time what had, nonetheless, already been said, and must tirelessly repeat what had, however, never been said. … it allows us to say something other than the text itself, but on condition that it is this text itself which is said, and in a sense completed’.⁶⁴ As commentators and exegetes, Caesarius and his predecessors were engaged in just this exercise: their readings of Genesis xviii and xix sought to excavate the text's implicit meaning. The teachings about the nature of God and Christ that they uncovered were partly conditioned by their respective doctrinal contexts and polemical needs: the appropriation of Justin's argument by subordinationist Christians thus undoubtedly contributed to Augustine's rejection thereof in favour of a more Trinitarian reading. By the same token, Caesarius’ ability to ‘recognise’ the Trinity in Abraham's visitors attests to a theological context in which God's Trinitarian nature was beyond dispute in Christian circles.

Most intriguing, however, are those early exegetes who ‘kicked against the goads’, whose exegesis was either far ahead of their time or dangerously close to being sunk in the changing tides of late antique ecclesial teaching. Origen's identification of Abraham's visitors with the Trinity at Mamre, in spite of his received ‘knowledge’ that the passage referred to Christ and his angels, is thus a captivating insight into the text's guidance of its exegete into still-foreign interpretive channels. By the same token, Hilary of Poities's struggle to retain not only a text but its time-honoured interpretation for the cause of orthodoxy demonstrates just how inseparable text and commentary had become in the minds of many patristic readers. The works of these authors, as well as their later adopters and adapters, provided room for the development of interpretive meaning for Genesis xviii alongside the Church's developing Christological and Trinitarian doctrine. The mysterious case of Abraham's visitors at Mamre thus offers an instructive example of the perichoresis of text and commentary, their mutual inherence and continuing procession.