LUTHER was soon to leave the convent for an enlarged sphere of labor. Staupitz (who had become a friend of Luther's since they met in the convent) had spoken of him to Frederick the Wise, Elector of Saxony, and that prince invited Luther to be a professor at the University of Wittenberg. Luther felt it his duty to accept the invitation. He quitted Erfurt in 1508.
Now he had to teach philosophy, while his real desire was to unfold the word of God. "I am very well by God's favors," wrote he to his friend John Braun, curate of Eisenach, “except that I am compelled to give my whole attention to philosophy. From the moment of my arrival at Wittenberg I have longed to exchange this study for theology: but I mean that theology which seeks the kernel of the nut, the pulp of the wheat, the marrow of the bone;" meaning the true theology of scripture, and not the theology of the age. "However, things may proceed; God is God; man always errs in his judgment; but this is our God forever and ever; he will be our guide unto death." Thus did Luther evince his confidence in God; and indeed his study of philosophy proved to be of great value to him afterward. When it was sought to set it up as an authority, he could pull it all to pieces and show that it had no solid foundation. Scripture must be put in its place.
However, in the next year he became Bachelor of Divinity, and then he daily expounded the scripture to the pupils. This he did in such a clear and simple way that even some of the other professors used to mingle with the pupils to hear his lectures. Mellerstadt, who was sometimes called "the light of the world," was one of his hearers. "This monk," said he, "will put all the doctors to the rout. He will introduce a new kind of doctrine, and will reform the whole church. He builds upon the word of Christ, and no one in this world can either resist or overthrow that word, though it should be attacked with all the weapons of philosophers.”
Luther, in coming to Wittenberg as a professor, had not ceased to be a monk. They set apart a cell in the convent of the Augustine’s in that city for his use, and there he spent many an hour over his Bible. One day, as he was reading the first chapter of the epistle to the Romans, he came to verse 17 and read "The just shall live by faith." These words arrested him. There was a new life possessed by some, and that new life was the fruit of faith. How simple, and yet how grand! It entered into his very soul with a flood of light, and, as we shall see, again and again it recurred to his memory in after days with new life and power.
Luther was next invited to preach in the convent pulpit, but he repeatedly declined. "No, no," said he, "it is no light thing to speak to men in God's stead." Staupitz however was not to be denied, and at length he carried his point. Luther began to preach. "In the middle of the square of Wittenberg," says D'Aubigne, "stood an old wooden chapel, thirty feet long, and twenty broad, whose walls, propped on all sides, were falling to ruins. A pulpit, made of planks, raised three feet above the ground, received the preacher." It was in this humble place that Luther began to preach. One has compared it to the stable in which our Lord was born.
The place was certainly not attractive, but the preaching was; indeed it created quite a sensation. His predecessors had often been ignorant men, some not Christians, and they had aimed rather to please the people, than to do them good. But Luther knew the value of salvation, and nothing less would do for him than to preach the gospel in the fullest and freest way he knew how. His hearers were astonished and arrested. The place was soon too small, and he was chosen to preach in the city church of Wittenberg. Luther had soon recovered from his dread of preaching and was now in his true element. He delighted to preach and expound the scripture; which was all the more striking as it was in strong contrast not only with what had been preached at Wittenberg, but what was to be heard in the thousands of churches scattered over the empire. In God's truth a light had sprung up amid the general darkness-a light from heaven, and Luther was the bearer of it.