He is the author of Religious Polemic and the Intellectual History of the Mozarabs, c. 1050-1200 (1994); Reading the Qur’an in Latin Christendom, 1140-1560 (Philadelphia: University of Pennsylvania Press, 2007); and, with Brian A. Catlos and Mark D. Meyerson, of The Sea in the Middle: The Mediterranean World, 650-1650 (Berkeley: University of California Press, 2022). With Sergio LaPorta, Alison Vacca et al., he is editor and translator of A Connecting Polemic in the Medieval Mediterranean: The Correspondence of Leo III and ʿUmar II (Chicago: Institute for the Study of Ancient Cultures, 2025). He is currently writing a book entitled Beyond the Mediterranean: The Intellectual Venture of Ramon Martí OP, 1250-84. His research has been supported by fellowships from the Rockefeller and Guggenheim Foundations as well as the National Endowment for the Humanities. In 2025-26, he was a Member of the Institute for Advanced Study in Princeton.