The two ideas that I briefly surveyed in sect. 1.3 are intimately linked in the thought of Theodore of Mopsuestia and Nestorius. Both men espouse what I call a two-act salvation scheme: they see humanity's natural condition as one of mortality and imperfection and view salvation as an advance to a higher, perfect state. Furthermore, they see salvation not so much as an elevation to divine life but rather as progress towards perfect human life, and this allows them to adopt a christology that distinguishes sharply between the Logos and the assumed man. What binds this two-act salvation scheme and a divisive christology together is Theodore's and Nestorius' concept of grace, an idea driven by the belief that God gives people those gifts (power, aid, and cooperation) that they will need in order to advance from the age of mortality to that of perfection. The relation between the assumed man and the Logos is a special case of the grace by which God interacts with people in general: God the Logos gives that man the power and co-operation he needs to be our pioneer in the march to the perfect age.
Therefore, in this chapter I will attempt to set the stage for my discussion of Cyril and Cassian by examining the concept of grace that lies behind, and that one could say even constitutes, Theodorean/Nestorian christology. While Nestorius was the one who actually ignited the christological controversy, scholars agree that he did little to advance the thought of Theodore and that it was largely the latter's theology that lay behind the dispute, 1 and therefore I will concentrate on Theodore. I will look first at his understanding of the two ages as the basis for his