This study explores the extent to which Mendelssohn’s Jerusalem engages with Protestant sources in its portrayal of rabbinic tradition, which will allow further light to be shed on the pivotal role of rabbinic Judaism and its representations within the emotionally charged polemics surrounding Jewish emancipation in eighteenth-century Prussia. This examination demonstrates that Mendelssohn’s idealized perception of rabbinic thought is deeply embedded in anti-rabbinic Protestant works, whose framework aids him in shaping his own unique outlook. By analyzing Mendelssohn’s deployment of the notion of contradiction, this article shows how his argumentative strategies in Jerusalem efficaciously counter well-known Protestant patterns of critique against rabbinic Judaism. By focusing on his idiosyncratic quotations and insinuations, it recovers the Christian works that he draws on and appropriates for his apologetic objectives and establishes that he uses Johann A. Eisenmenger for his depiction of the nature of rabbinic discursive practices while speaking out against “many a pedant” for their assertion that the rabbis disregarded the principle of noncontradiction. This article argues that Mendelssohn is alluding to eighteenth-century Protestant theologians who unreservedly follow Eisenmenger’s anti-rabbinic perspective and elaborates on how Mendelssohn entirely reframes this view as a conceptual strength of Judaism’s dialogical essence, thus rendering it compatible with the Enlightenment-based Weltanschauung.