Werrett (religious studies, Saint Martin's U.) has revised and expanded his 2006 doctoral dissertation in biblical studies at the University of St. Andrews. In it he examines the concept of ritual purity by comparing the purity rulings of the Dead Sea Scrolls with their biblical counterparts. He considers each relevant document in isolation first, and compares them with other documents in the group only after extensive exegesis. His conclusion is that they disagree as much as they agree, bringing into question many of the dominant assumptions about the coherence of the collection and of the community that created it. Annotation ©2008 Book News, Inc., Portland, OR (booknews.com)