Oberman demonstrates how the simplifications and rigidities of modern historiography have obscured the existential spirits of such great figures as Luther and Calvin. He explores the debt of both Luther and Calvin to medieval religious thought and the impact of diverse features of "the long 15th century" - including the Black Death, nominalism, humanism, and the Conciliar Movement - on the Reformation.

The late Heiko A. Oberman, one of the twentieth century's great historians of the Reformation, was at the time of his death Regents' Professor of History at the University of Arizona. He was the author of many books, including the definitive biography of Martin Luther, Luther: Man Between God and the Devil. Donald Weinstein is professor emeritus of the Department of History at the University of Arizona.

"Oberman is bracing, fresh, and daring. In this book he continued his lifelong assault upon modern complacency and our overweening sense of superiority to the past." H. C. Erik Midelfort, University of Virginia