In ancient Jewish culture the ideas of purity and impurity defined the socio-cultural boundaries between Jews and Gentiles. Hayes argues that different views of the possibility of conversion, based on varying ideas about Gentile impurity, were the key factor in the formation of Jewish sects in the second temple period, and in the separation of the early Christian Church from what later became rabbinic Judaism.

In these articles from Tradition: A Journal of Jewish Thought, US and foreign rabbis, professors of Jewish studies, law, and philosophy, and an assistant attorney general for the state of New York all lend their views on the place of conversion in Jewish theology. While the articles are written from different perspectives, the contributors are united in their allegiance to the authority of the classical halakha and the belief that the pressure to recognize non-Jews who lack religious commitment leads to the erosion of halakhic standards. A shorter version of the book appeared 20 years ago under the title The Conversion Crisis. This edition adds two new articles: a review of Avi Sagi and Zvi Zohar's Transforming Identity: The Ritual Transition from Gentile to Jew; Structure and Meaning, which imposes a halakhic critique on Sagi and Zohar's attempt to reorder the Talmudic literature on conversion, plus a response from Sagi and Zohar. The book lacks a subject index. Feldman is editor emeritus of Tradition. Wolowelsky is dean of the faculty at the Yeshivah of Flatbush and an associate editor of Tradition. Annotation ©2011 Book News, Inc., Portland, OR (booknews.com)