The doctrine of theosis means a salvation that is the deification of the saved. The saved actually become God. This unusual doctrine lies at the heart of Nicholas of Cusa's (1401-1464) mystical metaphysics. It is here examined for the first time as a theme in its own right, along with its implications for Cusanus's doctrine of God, his theological anthropology, and his epistemology. Nancy Hudson opens her book with a historical introduction of the term ""theosis"" from its roots in the Greek fathers (Gregory of Nyssa and Maximus the Confessor) to its mature development in Pseudo-Dionysius....