Luther wrote the 119 letters in this volume between 1507 and 1522, during the momentous years that saw him change from an obedient and determined priest of his Order to a vigorous critic of the sale of indulgences and finally to the leader of a reformed church. In these letters Luther discusses his posting of the Ninety-five Theses, the disputations at Heidelberg, Augsburg, and Leipzig, and the bull excommunicating him.