Christine Hayes is Sterling Professor Emerita of Jewish Studies at Yale University, and a Senior Research Fellow at the Shalom Hartman Institute of North America. She is the author of Gentile Impurities and Jewish Identities and What's Divine about Divine Law? Early Perspectives. Jay M. Harris is Harvard College Professor and Harry Austryn Wolfson Professor of Jewish Studies at Harvard University. He is the author of How Do We Know This: Midrash and the Fragmentation of Modern Judaism.