Roman faith and Christian faith : Pistis and Fides in the early Roman empire and early churches This study investigates why faith (pistis fides) was so important to early Christians that the concept and praxis dominated the writings of the New Testament. It argues that such a study must be interdisciplinary locating emerging Christianities in the social practices and mentalites of contemporary Judaism and the early Roman empire. This can therefore equally be read as a study of the operation of pistis fides in the world of the early Roman principate taking one small but relatively well attested cult as a case study in how micro societies within that world could treat it distinctively. Drawing on recent work in sociology and economics the book traces the varying shapes taken by pistis fides in Greek and Roman human and divine human relationships: whom or what is represented as easy or difficult to trust or believe in; where pistis fides is deferred and reified in practices such as oaths and proofs; how pistis fides is related to fear doubt and scepticism; and which foundations of pistis fides are treated as more or less secure. The book then traces the evolution of representations of human and divine human pistis in the Septuagint before turning to pistis pisteuein in New Testament writings and their role in the development of early Christologies (incorporating a new interpretation of pistis Christou) and ecclesiologies. It argues for the integration of the study of pistis pisteuein with that of New Testament ethics. It explores the interiority of Graeco Roman and early Christian pistis fides. Finally it discusses eschatological pistis and the shape of the divine human community in the eschatological kingdom.