Luther in his early years came of age in a late medieval setting from which he was not prone to depart during these years. His father, Hans, strongly impressed upon his son a responsibility to improve his lot by climbing the social ladder, for in his eyes that was what a dutiful son should do. But young Luther declined to follow this path and instead entered the order of the Augustinian Eremites in Erfurt in 1505. Here, he found pious advisors, chiefly John Staupitz, his patron over the course of the following years. Luther’s first mass in 1507 symbolically marked the break with his father. From that time forward, Luther spent his time as a monk, priest, and theologian. Somehow he became involved in controversies within his order, which led him to make a journey first to Rome in 1511/12, and, following his return, to Wittenberg. Here, he developed his hermeneutical method lecturing on the Psalms and Paul. In this time, his religious thought developed, but not all at once, as Luther himself often reported, but gradually. Here he was influenced not only by Paul and Augustine, but also by the late medieval mysticism he came to know through the sermons of John Tauler. Reading these sermons in 1515/16 he inserted many marginal notes, and they show that he was a proponent of an inward piety focused on the concept of faith. At this time, he was still attached to his spiritual advisor John of Staupitz. Mainly through the temptation occasioned by the doctrine of predestination, Luther developed some helpful insights, which led him to acknowledge Jesus Christ as the only Savior. His insights took him beyond the medieval framework and made him a reformer who was first and foremost focused on a new approach to the academic training of the theologian.