This book offers a new proposal for the origin of Luther's two kingdoms idea and a strong correction of recent scholarly interpretations of the idea. William Wright argues that a key source for Luther's idea was Renaissance humanism, especially as it engendered skepticism through its critical methods and polemics against scholasticism. According to Wright, Luther found crucial answers to such skepticism in Lorenzo Valla's conviction that earthly matters must be known and studied differently from spiritual matters. Building upon this, Luther's two kingdoms concept became his Weltanschauung, his worldview. It shaped the whole body of his theology, including themes such as law and gospel, flesh and spirit, reason and faith, and the sacraments. Thus, Wright argues that the prevailing view of Luther's two kingdoms since the nineteenth century—that it is a political doctrine, perhaps even meant to justify irresponsible conduct in earthly affairs—is decidedly incorrect. The book proceeds by describing modern interpretations of Luther's two kingdoms idea, by examining early Italian and later northern humanism, and finally by examining the contexts in which Luther utilized the idea and how he applied it to Christians' earthly life.

Though Wright's criticisms of recent interpretations of Luther's two kingdoms are not unique, Wright plows new and helpful ground in exploring the Renaissance sources and in finding pervasive evidence of the two kingdoms idea penetrating every corner of Luther's theology. This is a welcome addition to the literature and a helpful antidote to lingering misperceptions about this crucial aspect of Luther's thought.