Additions From an Apostate: Petrus Alfonsi and a Shift in Anti-Jewish Polemic

Abstract

In the Twelfth Century, Petrus Alfonsi converted from Judaism to Christianity and wrote his Dialogi contra Iudaeos. In this polemical text, Alfonsi utilized Islamic science and reason to attack Judaism and the Talmud as being irrational. The Dialogi contra Iudaeos deviated from the tradition of Augustine and successfully reintroduced the accusation of intentional deicide along with the first efficacious attack on the Talmud. The arguments developed in the Dialogi contra Iudaeos provided ideas that would influence the Talmud Burnings of Paris in 1242.