This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.
Augustine of Hippo tells the story himself, in the Confessions: before his conversion to Christianity, in the years he was still searching for an account of God and evil he could actually accept, he read certain books of the Platonists, almost certainly Plotinus and Plotinus's own student Porphyry in Latin translation, and found in them something he had been unable to find anywhere else, a way to think about a wholly immaterial reality without picturing it as simply a very large, very powerful physical thing extended through space. Augustine had struggled for years with exactly this difficulty: he had spent roughly nine years as a hearer among the Manichaeans, whose dualism pictured good and evil as two competing physical substances at war in the world, and he could not conceive of God, or of evil, in genuinely non-physical terms until Neoplatonism gave him the conceptual tools to do it. From Plotinus's system he took, and transformed, several ideas that became load-bearing pieces of Christian theology. The absolute transcendence and simplicity of Plotinus's One, beyond every category and determination, became a philosophical vocabulary for describing the transcendence of the Christian God. Plotinus's account of evil as not a positive substance or force at all, but a privation, an absence or falling away of the good the way darkness is simply the absence of light rather than a thing in its own right, gave Augustine his answer to the problem that had defeated his Manichaean years, evil is real as a lack, not real as a competing power, which let him affirm both that the world God made is good and that evil genuinely occurs within it. Augustine's use of Neoplatonism, it is worth stressing, was never uncritical adoption, he rejected the impersonal necessity of Plotinus's emanation scheme in favor of a God who creates freely out of nothing, addressing the relation of soul to body within his own doctrine of creation rather than the Neoplatonic scheme he had inherited it from. But the vocabulary, transcendence, simplicity, the privative theory of evil, the ascent of the soul through stages toward an immaterial highest good, travelled from a pagan philosopher's school in third century Rome into the center of Latin Christian theology, and did so because Augustine judged it, honestly, to be the best available tool for the job.