Irenaeus’ Theology in Second-Century Platonism and Christianity

Abstract As scholars have come to appreciate Irenaeus’ use of philosophy, emphasis has fallen on his use of pre-Socratic traditions. This emphasis stands in stark contrast to the typical emphasis scholars place on Platonic themes in second-century Christian theologies. This article argues that Platonic resources, the definition of God as simple and incomposite, the Platonic viae, and reasoning from ‘oneness’ to ‘unlimitedness’, play a key role in Irenaeus’ theology, governing his interpretation of pre-Socratic materials, including Irenaeus’ version of the well-known Xenophanes quotation (fr. 24) and materials Irenaeus apparently draws from Pseudo-Aristotle’s On Melissus, Xenophanes, and Gorgias. Irenaeus, furthermore, draws a logical connection between God’s simplicity and the doctrine that there is one God to the exclusion of others, as he says, thereby pressing Platonic doctrine into the service of his distinctly Christian theological convictions. The upshot of all this is a deeper appreciation first for the sophistication of Irenaeus’ own theology, and second for Irenaeus’ role in engaging and advancing Christian philosophical theology.