Inter-religious interactions between Muslims and Jews in Yemen were mediated by practices of vernacular religion, notably the use of amulets, performed by Jews and Muslims alike. The making of amulets combined material and textual elements. Jewish craftsmen created silver necklaces containing amulets, while their content was based on an interpretation of magical guide-books. These manuscripts offer a complex matrix of Muslim and Jewish sources, and contain a bewildering mosaic of languages, Arabic, Hebrew and Aramaic. Composing and using such books required acts of translation, interpretation and mediation of knowledge by Jewish-Yemeni scholars. By utilizing both ethnographic and textual methods, this lecture will examine the question of how amulets mark and blur religious boundaries between Judaism and Islam.