The 1518 Proceedings at Augsburg Suzanne Hequet Martin Luther's writing of the 95 Theses in 1517 has been celebrated this past year as the 500th anniversary of the event that sparked the Reformation. Still, 2018 marks an opportunity to focus on another key moment that defined the early Reformation. Specifically, in 1518 Luther faced a papal legate, Cardinal Cajetan, in meetings held during an imperial diet in Augsburg. The 500th anniversary of this meeting lifted up Luther's arguments on the nature of faith and certainty—arguments that shook Cajetan's Thomist theology, and thereby exposed papal authority as the crux of issues surrounding reform. In 1517 Luther's academic dispute over indulgences, which began with the distribution of the 95 Theses on 31 October, was followed by two kinds of attacks. To begin with, theologians north of the Alps, such as Johann Tetzel and Conrad Wimpina, issued counter-theses and arguments. When Archbishop Albrecht of Mainz sent the Theses to Rome, however, the academic dispute automatically became an ecclesiastical case, perhaps expanded by a separate brief by Dominicans like Tetzel. First to answer Luther's Theses in Rome was the papal court theologian, Silvester Prierias, who in July 1518 published the Dialogus, in which he argued that Luther misunderstood his own presuppositions and needed especially to understand papal authority. This publication was an important first step in the papal decision to initiate formal proceedings against Luther.1 [End Page 60] Meanwhile, by May 1518, Luther had written a defense of the 95 Theses, the Explanations of the Ninety-Five Theses, dedicated to Pope Leo X and authorized for publication by Luther's ordinary, the bishop of Brandenburg, but not published until August.2 By the end of August, following a meeting of the German chapter of the Augustinian Order in April 1518, Luther published his response to Prierias, insisting on a coalition of authorities that he would later use in his encounter with Cajetan: reason, the fathers of the church, the official church decrees (canon law) and, above all, the Bible. In the summer of 1518 an imperial diet convened in Augsburg, to which the pope sent his legate, Cardinal Cajetan (also known as Tommaso de Vio). Already on 7 August Luther had received a summons to face trial in Rome. Matters had moved beyond learned debate to something far more serious, and Luther did not hide his alarm. To complicate matters, during Lent 1518 Luther had delivered a sermon on excommunication and its abuse by church authorities. Opponents had composed a distorted set of theses on the subject under Luther's name and circulated them at the diet.3 The emperor Maximilian was outraged and called for action. On 23 August the pope delivered to Cajetan a summons that Luther appear in Rome to answer charges of heresy. On 11 September Cajetan received permission to interrogate Luther in Augsburg and either receive his recantation or condemn him. The pope also sent word to Luther's prince, Elector Frederick, to assist in an arrest, if such action was necessary.4 Frederick delayed a few weeks, but then, in a shrewd political move, requested that Luther appear in Augsburg in late September under a letter of safe conduct. Thus, in early October, Luther set out for Augsburg. En route, he was joined in Nuremberg by Wenceslas Linck, a fellow Augustinian. At Augsburg the proceedings between Luther and Cajetan consisted of three meetings from 12–14 October 1518. Having received his letter of safe conduct for travel in the city of Augsburg, Luther met with the Cardinal for the first time on 12 October. In the following text, written after he returned to Wittenberg on 31 October 1518, Luther recounted his meetings with Cajetan at Augsburg: [End Page 61] The Proceedings of Friar Martin Luther, Augustinian, with the Lord Apostolic Legate at Augsburg5 To the Godly Reader, Friar Martin Luther Extends Greetings Now, dear reader, what I am doing is this: I see that pamphlets are being published and various rumors are being spread concerning my activities at Augsburg, although I really accomplished nothing more there than the loss of time and money. Probably, however, it was enough of...