He had spent three eventful years in the cloister at Erfurt. But these years were not lost to him. The general cultivation of his mind, the discipline of his soul, his study of Hebrew and Greek, were so many branches of needed education for his future career in the Lord's service. Besides, it was the place of his spiritual birth, and the place where he first heard of justification by faith—that divine doctrine on which so much of his subsequent work was built.
In the year 1507 he was ordained a priest, at which ceremony his father was present though still dissatisfied with the course of his son. Luther had now received power from the bishop to offer sacrifice for the living and the dead, and to convert, by muttering a few words, the unleavened cake into the real body and blood of the Lord. Luther submitted to and accepted these popish pretensions, though against his convictions, and with fear and trembling; but his soul never completely recovered from the effects of this blasphemous ordination. A judicial blindness as to the scriptural simplicity of the Lord's supper settled down upon his mind. He was enabled, by the grace of God, to throw off and denounce many of Rome's superstitions, but never fully her crowning enormity, transubstantiation.
Staupitz, the faithful friend and patron of Luther, placed him, at the age of twenty-five, in a position suited for the display of his powerful and active mind, and the further development of his character. He was invited by the Elector Frederick, at the suggestion of the vicar-general, to occupy a chair of philosophy in his rising university. He removed to Wittemberg in the year 1508. But though called to be a professor he did not cease to be a monk; he lodged in a cell in the Augustinian convent. The subjects on which he was appointed to lecture were the physics and dialectics of Aristotle. This was uncongenial employment for one who was hungering and thirsting after the word of God. Neither physical science nor moral philosophy suited the spirit of his mind. But again, we may say, it was part of his needed education. He who had passed through the cloister must now occupy for a time the chair of scholastic philosophy, that he might be better fitted to expose the evils, and combat the errors, of both systems, and emancipate the minds of men from their influence.
In the mean time, though he was attracting the youths of Wittemberg by the force and style of his lectures, he was zealously applying himself to the study of Greek and Hebrew. His desire was to drink at the fountain; and He who saw the great desire of his heart and the labor of his life opened up the way for him. In a few months after his arrival at the university he obtained the degree of Bachelor of Divinity, which entitled him to lecture on theology, or on the Bible. He now felt himself in his proper sphere, and determined to communicate that only which he learned from the word of God. His first discourses were on the Psalms, and then he passed to Paul's Epistle to the Romans.
His precious meditations on these portions in his quiet cell, both at Erfurt and Wittemberg, gave a character to his lectures altogether new. He spoke, not merely as an eloquent schoolman, but as a Christian who felt the power of the great truths he taught. When he reached, in his expositions, the last clause of Rom. 1:17, "the just shall live by faith," a light, we may say, beyond the brightness of the sun, filled his whole soul. The Spirit of God clothed the words with
light and power to the understanding and to the heart of Luther. The grand doctrine of justification by faith alone he received into his heart as from the voice of God. He now saw that eternal life was to be obtained not by penance but by faith. The whole story of the German Reformation is connected with these few words. In their light he explained the scriptures of the Old and New Testament; by their truth he exposed the falsehoods of popery, he thrilled the heart of Europe, he brought the reign of imposture to an end, and accomplished the great Reformation. Alone he stood before all authority—before all the world—on the truth of the word of God, "the just shall live by faith." God's word is true, popery is a lie; the one must fall, the other must triumph; truth is health to the soul, a lie is deadly poison. These principles of eternal righteousness were now firmly fixed in the heart of Luther by the Spirit of God; and, simple as they may appear, he was enabled, through faith in the word of God, to triumph over popes, bishops, clergy, kings, and emperors, raising the standard of salvation through faith in the Lord Jesus Christ, without works of law.
The great work was now begun, but the workman had still some lessons to learn.