The 'tractate' of conversion - BT YEB. 46-48 and the evolution of conversion procedure

Tractate Yebamoth of the Babylonian Talmud contains a long unit devoted to the procedure of conversion (Yeb 46a-48b). Form analysis of the unit reveals its design as a 'tractate within a tractate.' The unit is a collection of discussions on baraitas. It follows various literary conventions, such as placing a full description of the procedure towards the end and concluding with haggadic material and a verse of comfort. A variety of methods are applied in order to identify the unique Babylonian tendencies documented in this unit. Synoptic comparison to tannaitic parallels demonstrates the growing stringency and institutionalization of the rabbinic conversion procedure. A common structural feature of each discussion is the ending with an amoraic statement that reassure the halakhic validation of the stringent views. Stammaitic comments and the overall literary structure of the unit also seem to confirm this tendency. This unit demonstrates Babylonian efforts to further reinforce the boundaries of Jewish identity. The traditions as preserved in this unit show that Babylonian proclivities were gradually attributed to earlier Palestinian authorities. The most prominent example is the institution of the court for conversion. This is a Babylonian construct, systematically presented in places where it is missing in Palestinian rabbinic sources. In our unit it is also attributed to early Palestinain amora'im, and even to a tanna. Not only did the Babylonian sages change the model of conversion from witnessed circumcision (and later immersion) to court controlled procedure, they also projected their innovations onto earlier generations.