The Jewish culture of the Hellenistic and early Roman periods established a basis for all monotheistic religions, but its main sources have been preserved to a great degree through Christian transmission. This Guide is devoted to problems of preservation, reception, and transformation of Jewish texts and traditions of the Second Temple period in the many Christian milieus from the ancient world to the late medieval era. It approaches this corpus not as an artificial collection of reconstructed texts–a body of hypothetical originals–but rather from the perspective of the preserved materials, examined in their religious, social, and political contexts. It also considers the other, non-Christian, channels of the survival of early Jewish materials, including Rabbinic, Gnostic, Manichaean, and Islamic. This unique project brings together scholars from many different fields in order to map the trajectories of early Jewish texts and traditions among diverse later cultures. It also provides a comprehensive and comparative introduction to this new field of study while bridging the gap between scholars of early Judaism and of medieval Christianity.