Henri Bouillard introduced us to the idea that, while in Italy, Thomas Aquinas, likely with access to the Papal Court’s library, encountered Augustine’s two later anti-Pelagian works De Praedestinatione Sanctorum and De Dono Perseverantiae. All evidence indicates that these tracts influenced Aquinas’s account of grace. Bouillard’s research is groundbreaking, but not complete. Having confined himself to the topics of grace and conversion, Bouillard does not expound on a second insight Thomas gleaned from Augustine in those works. Further evidence shows that Aquinas’s Augustinian discovery altered how he thought about the human agent’s ability to merit the grace of perseverance. This has ramifications for how Thomas understands one’s ability to continue in a life of virtue simpliciter.