Why did Medieval Jews Criticize Christianity?

Prof. Daniel J. Lasker is the Norbert Blechner Professor of Jewish Values (emeritus) in the Goldstein-Goren Department of Jewish Thought at Ben-Gurion University of the Negev, Beer Sheva, Israel. He holds a Ph.D., M.A. and B.A. from Brandeis University, and also studied at Hebrew University. Prof. Lasker has taught at Yale University, Princeton University, University of Toronto, Ohio State University, University of Texas, University of Washington, Boston College and other institutions. He is the author of over two hundred fifty publications in the fields of medieval Jewish philosophy, especially on the thought of Rabbi Judah Halevi; the Jewish-Christian debate, including the edition of a number of central Jewish polemical texts; and Karaism. His most recent books are From Judah Hadassi to Elijah Bashyatchi: Studies in Late Medieval Karaite Philosophy (Leiden/Boston: Brill, 2008); The Sage Simhah Isaac Lutski. An Eighteenth-Century Karaite Rabbi. Selected Writings (Jerusalem: Ben-Zvi Institute, 2015 [Hebrew]); and (with Johannes Niehoff-Panagiotidis and David Sklare), Theological Encounters at a Crossroads: A Preliminary Edition of Judah Hadassi’s Eshkol ha-kofer, First Commandment, and Studies of the Book’s Judaeo-Arabic and Byzantine Contexts, Leiden/Boston: Brill, 2019.

In the Middle Ages, Jewish authors produced a large number of compositions in which they criticized the Christian religion. These works are characterized by a broad array of argumentation, including exegetical, historical and rational refutations of Christian texts and doctrines. The standard explanation of this phenomenon is that Jewish criticism of Christianity was a purely defensive move in light of Christian missionary campaigns and threats against Judaism. A more nuanced analysis leads to the conclusion that the Jewish critique of Christianity was a function of many factors, including a desire for Jewish theological self-understanding, and was not always a reaction to a specific Christian challenge.