This collected volume contains thirteen papers by Hanns Christof Brennecke demonstrating how Christianity in the Imperial Age and Late Antiquity is embedded in the context of the Imperium Romanum. The topics range from the early conflicts between Christianity and the pagan world to questions of Trinitarian theology and Christology and on to analyses of Syrian monasticism. With their detailed analyses of the sources, these papers have had a lasting influence on research in the field.