This dissertation focuses upon the baptismal theology of the fourth century bishop-theologians Basil the Great, Gregory of Nazianzus and Gregory of Nyssa, particularly their use of Paul's Romans 6 image of dying and rising with Christ. Though the theology of John 3 and the model of Jesus' baptism in the Jordan were dominant in the churches of the East prior to the fourth century, from then on Romans 6 theology surges to prominence. Rather than seeking to explain how the Cappadocians fit into that shift, this dissertation focuses on how the death imagery of Romans 6 serves the theological purpose of linking baptism to the Christian life as a whole. This is an investigation of the Cappadocians' theological assessments of what baptism accomplishes and what life should be like after baptism. According to them, baptism must be preserved and even validated by a holy life: a life of moderation characterized by self-control, detachment from the flesh and worldly concerns, and generous care for the poor. Chapter 1 sets the historical and theological context with summaries of: the development of the rites of initiation in the East (with emphasis on the importance of Jesus' baptism in the Jordan and the feast of Epiphany), the development of penance and theological views of postbaptismal sin, and the Christian and Hellenistic influences on the Cappadocian view of the life of philosophy. In Chapters 2-4 each of the Cappadocians is considered in turn. Each chapter includes a close reading of the baptismal texts. The names used for baptism, descriptions of the rite, accounts of the effects of baptism, and a consideration of the importance of Romans 6 (and John 3) theology are given particular attention. Also included is an assessment of each figure's account of the philosophical life. Drawing on ascetical texts, the topics of postbaptismal sin, death, and the connections between baptism and the philosophical life are considered. Chapter 5 draws on insights gained from each figure and offers a summary of their collective view of baptism, their use of Romans 6, and the connections they make between baptism and the philosophical life.