In his theses, Luther condemned the excesses and corruption of the Roman Catholic Church, especially the papal practice of asking payment—called “indulgences”—for the forgiveness of sins. At the time, a Dominican priest named Johann Tetzel, commissioned by the Archbishop of Mainz and Pope Leo X, was in the midst of a major fundraising campaign in Germany to finance the renovation of St. Peter’s Basilica in Rome. Though Prince Frederick III the Wise had banned the sale of indulgences in Wittenberg, many church members traveled to purchase them. When they returned, they showed the pardons they had bought to Luther, claiming they no longer had to repent for their sins.
Although Luther still considered his activities as directed toward reforms within the church, his opponents found his ideas heretical. In the following years several attempts were made to reconcile Luther to the church, but the basis of compromise was lacking on both sides. At a meeting with the papal legate at Augsburg in 1518, Luther refused to recant, and in 1519 in a public disputation with Eck in Leipzig he was forced to declare his stand as one at variance with some of the doctrines of the church.
Martin Luther thesis - Educational Writing
Amore et studio elucidande veritatis hec subscripta disputabuntur Wittenberge, Presidente R. P. Martino Lutther, Artium et S. Theologie Magistro eiusdemque ibidem lectore Ordinario. Quare petit, ut qui non possunt verbis presentes nobiscum disceptare agant id literis absentes. In nomine domini nostri Hiesu Christi. Amen.