There has been a good deal of helpful conversation over the past decade about the relationship between spiritual formation/sanctification and the nature or psychology of virtue development in Aristotle, Aquinas, and Positive Psychology. This has been a very needed conversation, for it has helped provide an anthropological/psychological model for a developed and rigorous approach to spiritual formation, sanctification, and flourishing. I want to discuss these benefits, while also presenting some of the inherent tensions between these traditions, particularly regarding the tension between flourishing and “natual virtue” without God and flourishing with God (fruits of the Spirit or “supernatural virtue”). I will argue that flourishing without God is a both a kind of health and a kind of sin or psychopathology; and that God’s “flourishing” or sanctification process may look at times very similar to and yet sometimes different to our everyday concept of flourishing or natural virtue. Included in this discussion will be the the distinction between the natural and “supernatural virtues,” the complex issue of continuity and discontinuity between them, and the developmental process of growth in these.