In her recent Calvin’s Ladder: A Spiritual Theology of Ascent and Ascension , Julie Canlis argues, following the work of Peter Wyatt, that Thomas displaces Christ from the center of his explanation of the “golden circle” of movement away from and return to God. Wyatt says that the circle is essentially complete after ST II-II, and ST III “does not belong integrally to it.”
Canlis herself argues that Thomas’s fateful mistake was in his doctrine of created grace: “Once Aquinas located ‘created grace’ in the soul, it began to take on a life of its own, displaying God – and sometimes more specifically the incarnate Christ – as the source of ascent. It is this substantial view of anthropology that sanctions a consideration of the soul in itself and that partially explains the flowering of medieval mystical treatises on the soul and its ascent.”
If accurate, this explains in large measure the need for the Reformation. The Reformation is not, in Canlis’ view, a rejection of the ascent motif, but a Christological re-centering of the motif.