141. Martin Luther was of peasant origin. His father was very poor, and was trying his fortune as a miner near the Harz Mountains when his eldest son, Martin, was born in 1483. Martin sometimes spoke, in later life, of the poverty and superstition which surrounded him in his childhood; of how his mother carried on her back the wood for the household and told him stories of a witch who had made away with the village priest. The boy was sent early to school, for his father was determined that his eldest son should be a lawyer. At eighteen, Martin entered the greatest of the north-German universities, at Erfurt, where he spent four years. There he became acquainted with some of the young humanists, for example, the one who is supposed to have written a great part of the _Letters of Obscure Men_. He was interested in the various classical writers, but devoted the usual attention to logic and Aristotle. [Sidenote: Luther decides to become a monk.] Suddenly, when he had completed his college course and was ready to enter the law school, he called his friends together for one last hour of pleasure, and the next morning he led them to the gate of an Augustinian monastery, where he bade them farewell and turning his back on the world became a mendicant friar. That day, July 17, 1505, when the young master of arts, regardless of his father's anger and disappointment, sought salvation within the walls of a monastery, was the beginning of a religious experiment which had momentous consequences for the world. [Sidenote: Luther's disappointment in the monastery.] Luther later declared that "if ever a monk got to heaven through monkery," he was assuredly among those who merited salvation. So great was his ardor, so nervously anxious was he to save his soul by the commonly recognized means of fasts, vigils, prolonged prayers, and a constant disregard of the usual rules of health, that he soon could no longer sleep. He fell into despondency, and finally into despair. The ordinary observance of the rules of the monastery, which satisfied most of the monks, failed to give him peace. He felt that even if he outwardly did right he could never purify all his thoughts and desires. His experience led him to conclude that neither the Church nor the monastery provided any device which enabled him to keep his affections always centered on what he knew to be holy and right. Therefore they seemed to him to fail and to leave him, at heart, a hopelessly corrupt sinner, justly under God's condemnation. [Sidenote: Justification by faith, not through 'good works.']