The study of polemics between religions in the late Sasanian-early Islamic era is a crucial albeit undertheorized field of study. This presentation explores how scholars can and cannot access textual data that speaks to the issue of interreligious dialogues. What are the sources for reconstructing polemics between Jews, Zoroastrians, Christians, and early Muslims, and how should scholars study them in light of questions of polemics? Does one need to limit oneself to works of literature that explicitly engage the outside world--such as the late Zoroastrian work, the Shkand Gumming Wizar--or are there polemics between the lines of legal and narrative writings? This paper will address these questions through a selected study of Jewish and Zoroastrian writings in circulation from around the sixth through tenth centuries C.E., including the Babylonian Talmud, Geonic, Karaite literature, and Zoroastrian Pahlavi literature.