Not Peace But a Sword provides a case study in religious radicalism, as exemplified by the Puritanism of the English Revolution. Based on sermons preached to the Long Parliament and other political bodies, Stephen Baskerville demonstrates how Puritan religious and political ideas transformed the English Civil War into the world's first great modern revolution. To understand why, Baskerville analyzes the underlying social changes that gave rise to Puritan radicalism. The Puritan intellectuals developed the sermon into a medium that conveyed not only popular political understanding but also a sophisticated political sociology that articulated a new social and political consciousness. In the process, they challenged the traditional political order and created a new order by appealing to the needs and concerns of a people caught up in the problems of rapid social and economic change. The book explores the social psychology behind the rise of Puritanism, as the Puritan ministers themselves presented it, through textual criticism of their own words, placing them in the mental context of their time, and offers a new understanding of the link between religious ideas and revolutionary politics.