After exploring Eliano’s participation in the burning of the Talmud in Rome in 1553, the introduction outlines the book’s central argument regarding the entanglement of Eliano’s Jewish past and Catholic identity. By exploring Eliano’s Jewishness, which I define as the burden that his Jewish past continued to bear on the formulation of his Catholic identity, I argue that Eliano’s missionary efforts allow us to unpack how sincere converts approached their new religious identities in an age of heightened anxiety regarding religious conversion. By thinking of Eliano as a palimpsest of religious identity formation – someone whose Jewish past continued to play a foundational role in the way he became and existed as a Catholic – the book contributes to our historiographical understanding of the role of the individual in constructing collective identities in the early modern Mediterranean and how individuals were agents of collective change. His story likewise illuminates how Catholic missionary activity was also a field in which missionaries used their efforts to promote the apostolic mission of the Catholic Church to construct fuller senses of themselves and secure their place as Catholics.