An engrossing dual biography and fascinating intellectual history that examines two key figures of European history—Erasmus of Rotterdam and Martin Luther—whose bitter rivalry gave rise to two enduring, fundamental, and often colliding traditions of philosophical and religious thought. “A stellar achievement. . . . Penetrating, unputdownable. . . . Massing makes plain that the fight between Erasmus, citizen of the world devoted to Jesus the teacher, and Luther, master of invective devoted to Christ the redeemer, marks out the ideological crossroads of our era.”—Todd Gitlin, author of The Whole World Is Watching