Gradually a new view of Christianity came to him. The head of the monastery bade him trust in God's goodness and mercy and not to rely upon his own "good works." He began to study the writings of St. Paul and of Augustine, and from them was led to conclude that man was incapable, in the sight of God, of any good works whatsoever, and could only be saved by faith in God's promises. This gave him much comfort, but it took him years to clarify his ideas and to reach the conclusion that the existing Church was opposed to the idea of justification by faith, because it fostered what seemed to him a delusive confidence in "good works." He was thirty-seven years old before he finally became convinced that it was his duty to become the leader in the destruction of the old order. [Sidenote: Luther becomes a teacher in the University of Wittenberg, 1508.] It was no new thing for a young monk, suddenly cut off from the sunshine and hoping for speedy spiritual peace, to suffer disappointment and fall into gloomy forebodings, as did Brother Martin. He, however, having fought the battle through to victory, was soon placed in a position to bring comfort to others similarly afflicted with doubts as to their power to please God. In 1508 he was called to the new university which Frederick the Wise, elector of Saxony, had established at Wittenberg. We know little of his early years as a professor, but he soon began to lecture on the epistles of Paul and to teach his students the doctrine of justification by faith. [Illustration: Luther] [Sidenote: Luther's visit to Rome.] Luther had as yet no idea of attacking the Church. When, about 1511, he journeyed to Rome on business of his order, he devoutly visited all the holy places for the good of his soul, and was almost tempted to wish that his father and mother were dead, so that he might free them from purgatory by his pious observances. Yet he was shocked by the impiety of the Italian churchmen and the scandalous stories about popes Alexander VI and Julius II, the latter of whom was just then engaged in his warlike expeditions into northern Italy. The evidences of immorality on the part of the popes may well have made it easier for him later to reach the conclusion that the head of the Church was the chief enemy of religion. [Sidenote: Luther teaches a new kind of theology.] Before long he began to encourage his students to defend his favorite beliefs in the debates in which they took part. For instance, one of the candidates for a degree, under Luther's inspiration, attacked the old theology against which the humanists had been fighting. "It is an error," he says, "to declare that no one can become a theologian without Aristotle; on the contrary, no one can become a theologian except it be without him." Luther desired the students to rely upon the Bible, Paul's writings above all, and upon the church fathers, especially Augustine.[275] [Sidenote: Luther's theses on indulgences.]