If one looks at John Cassian's writings in the light of the issues I have considered thus far, there are several ways in which his thought seems similar to that of Theodore and Nestorius. He places great emphasis on the human task of pursuing moral perfection, and he frequently depicts grace as God's assistance or power to help us in that task. His christological language sounds Theodorean as well: he refers to Christ's humanity with the concrete homo rather than the abstract humanitas, and he occasionally uses the expression homo assumptus. 1 However, there are other ways in which Cassian's christology appears to be decidedly Cyrillian: he unflaggingly champions the title Theotokos, and he locates the unity of Christ's person in the Logos.
This tension is widely recognized among commentators, and Cassian is usually believed to have been an inconsistent thinker. Scholars argue that while he was a master of the spiritual life, he was not a theologian of any consequence. 2 It is generally agreed that Cassian's De Incar. Dom. had no influence on the course of the Nestorian controversy other than that of confirming Celestine's prior prejudice against Nestorius, 3 and historians are