Luther was popular among his mates. He won his bachelor’s then his master’s degree and began the study of the law for which his father intended him. Suddenly with crushing disappointment to that ambitious father and to the amazed disapproval of his friends, he abandoned together the study of the law and the world itself and entered a monastery. [Sidenote: “What Must I Do to be Saved?”] It had not been his studies alone which had occupied the young man during his university course, but meditation upon the needs of his own despairing soul. We have every evidence that he led a pure and godly life, yet the weight of that sin to which all mankind is heir lay heavily upon him. To a man of his time there was but one way of escape--the monastery, in which he might work out his salvation. Vowed to celibacy, to poverty, to obedience, devoting himself to prayer and fasting, he might hope to be saved. If “Brother Augustine,” as he was called, had any fault as a monk, he erred upon the side of too strict obedience. He followed all the rules of the order, he fasted, he scourged himself cruelly. But still he found no peace. God appeared to him an implacable judge, whose laws it was impossible to keep. He wearied his fellow-priests with confessions and inquiries, but his heart was not at rest. [Sidenote: The Answer.] Finally, however, he found an answer to his question. Partly by the help of his superiors, chiefly by the aid of the Scriptures, which, contrary to the custom of the time, he studied diligently, he saw a new light. God was a kind Father who required only that his children should throw themselves in faith upon His grace, accepting Christ’s sacrifice for them. Good works were simply the natural expression of a soul already reconciled with God and could have in themselves no merit. If one simply believed, one was justified by his faith. That this doctrine was not that of the Church, Martin did not realize. But he was soon to learn that his discovery was not acceptable to his superiors. There came into the neighborhood a monk, Tetzel by name, selling those indulgences which had become a menace to spiritual life. Against him and his traffic Luther protested, first in a sermon and then in a series of ninety-five theses which he nailed to the door of the Castle Church.