No period of history was more formative for the development of Christianity than the patristic age, when church leaders, monks, and laity established the standard features of Christianity as we know it today. Combining historical and theological analysis, Christopher Beeley presents a detailed and far-reaching account of how key theologians and church councils understood the most central element of their faith, the identity and significance of Jesus Christ. Focusing particularly on the question of how Christ can be both human and divine and reassessing both officially orthodox and heretical figures, Beeley traces how an authoritative theological tradition was constructed. His book holds major implications for contemporary theology, church history, and ecumenical discussions, and it is bound to revolutionize the way in which patristic tradition is understood.