In this thesis, I argue that life and soul as analyzed in De Anima are examples of what Aristotle calls a "[special characters omitted]" structure, a structure in which various things are said to be living in relation to one thing, which is the central meaning of life. The various kinds of soul and the living activities they exhibit are all to be understood in reference to the most complete and explicit sense of living, which is God's activity, the activity of thinking. God's thinking is the perfect paradigm of all living beings, and each living being and its characteristic living activities approximate this paradigmatic or ideal kind of life to greater or lesser degrees. Every kind of living being is striving to exhibit certain features of the life of God's thought to the extent that it is able as determined by its own particular nature. I analyze Aristotle's account of each level of ensouled life (nutrition, sensation, and thinking), in order to show how all living things share a common structure, expressing in different degrees of explicitness what is most fully expressed in God's life of contemplation. Through an analysis of the various activities and kinds of soul treated by Aristotle in his hierarchy of living activities, I show how these chief characteristics of the divine activity become progressively clearer and more explicit as one moves up the hierarchy of life. According to my interpretation, the whole argument of the De Anima is an account of the unfolding of soul from its most primitive appearance in nutrition to its complete actualization in thinking. This reading of Aristotle's De Anima demonstrates how his psychological and biological thought cannot be properly understood apart from his theological conception of God as life, and offers a new explanation of the treatise's unity of purpose and structure.