Apostasy: Defining the Boundaries of Jewishness in Classical Rabbinic Sources. Do Rabbinic sources address apostasy from an ethnic or religious perspective? As we will see through a close reading of a few key texts, the answer is “yes.” We will analyze them one by one, in an effort to extract competing values and frameworks on Jewishness. Each topic engages a different dimension of apostasy, exploring its impact on ritual (both private and public), kinship, and the fabric of communal life.