One of the conversion stories related to Augustine in the run-up to his own conversion was that of the philosopher and orator Marius Victorinus, who had translated the “books of the Platonists” that Augustine encountered in Book 7. What he does not tell us, however, is how important Victorinus was, not only as an exemplar of boldness in confessing Christ, but in shaping Augustine’s own reading of Plotinus. This chapter compellingly lays out Victorinus’ influence on Augustine’s Trinitarian theology as expressed in a brief and bewildering passage in Book 13. It shows that wherever Augustine departs from Plotinus, he does so in a way that he found in Victorinus; Victorinus also taught Augustine distinctions and arguments from Platonic and Aristotelian metaphysics that he could not have known from other Latin texts available to him. Through Augustine, then, Victorinus had a much larger influence on the history of metaphysics than has been appreciated up to now. Moreover, we find that “Augustine’s common designation as ‘Platonist’ would be more precise if it were revised to ‘Victorine Neoplatonist.’”