" When a burdened Augustinian friar in Wittenberg in October 1516 lamented in a letter how busy he was, no Reformation was in sight. Only Luther’s religious anxiety and his pastoral concern for Christian souls were present. By the summer of 1521, Martin Luther is Europe’s most famous man and its all-time bestselling author. "

― Brad S. Gregory , Rebel in the Ranks: Martin Luther, the Reformation, and the Conflicts That Continue to Shape Our World