What is the church? What does it mean to be a member of the church? This book examines how the earliest Christian theologians in the Latin West understood the nature, ends, and boundaries of the church. By analyzing the thought and practices of figures such as Tertullian of Carthage, Cyprian of Carthage, Augustine of Hippo, and Pope Leo the Great, James K. Lee shows how early Latin theologians forged distinctive views of the church as one, holy, catholic, and apostolic. Lee argues that according to the Latin fathers, the church was one complex reality with visible and invisible aspects that could be distinguished but not separated. God could work outside of the church’s visible bounds, yet all who were saved were joined to the church’s invisible bond of charity. The church’s unity was found in charity, and for the early Latin fathers, there was no salvation outside of the church. In addition, Lee demonstrates the trajectory from an exclusivist ecclesiology to a more inclusive understanding of church membership in the development of Latin ecclesiology over the course of the first five centuries of Christianity.