This book examines the ways in which two distinct biblical conceptions of impurity-'ritual' and 'moral'-were interpreted in the Hebrew Bible, the Dead Sea Scrolls, rabbinic literature, and the New Testament. In examining the evolution of ancient Jewish attitudes towards sin and defilement, Klawans sheds light on a fascinating but previously neglected topic. 'This volume makes a major contribution to the study of Ancient Judaism and Christianity. Professor Klawans has disentangled some confusing threads of ancient thinking about purity and has revealed a complex, nuanced array of perspectives to be found in our documentation. Those who wish to homogenize ancient Jewish thinking on the subject will hence forth be without excuse.'--Anglican Theological Review 'Jonathan Klawans makes an important contribution to scholarship on ancient Judaism by providing a fresh look at the relationship between sin and impurity. Klawans writes well; he is concise, well-organized, and usually very clear. I recommend this book for all professors or students of ancient Judaism or early Christianity.'--Review of Biblical Literature 'Klawans has offered some very helpful illumination, particularly to the study of the New Testament. The clarity and simplicity of his thought is very attractive, and throws light into some very obscure corners of ancient thought.' --Journal of Theological Studies