In 1510, Luther was dispatched to Rome on official monastic business. He was eager to visit that "Most Holy City," but he returned disillusioned and disgusted by its laxity and great immorality. On his return, he is finally persuaded by Staupitz to teach full time. In 1512, Luther is promoted to Doctor of Theology, and shortly thereafter begins preaching at the city church in Wittenberg.

Between 1513 and 1517, Luther taught on the Psalms, Romans and Galatians. These studies laid the foundation of the themes that would be at the very heart of the Reformation.