By this time Erasmus had attained his highest point. As years went on his activity continued unabated, his fame grew and his material circumstances reached a level at which he was far above want and could gratify his generous impulses freely. But a cloud arose which overshadowed him; and when it broke--long after Erasmus's death--it overwhelmed Europe. The causes which raised it up were not new. For centuries earnest and religious men--Erasmus himself among the number--had been protesting against evil in the Church. In December 1517 Martin Luther, a friar at Wittenberg, created a stir by denouncing a number of the doctrines and practices of the Church; and when the Pope excommunicated him, proceeded publicly to burn the Papal Bull with every mark of contempt. From this he was driven on by opposition and threatened persecution, which he faced with indomitable courage, to a position of complete hostility to Rome; endeavouring to shatter its immemorial institutions and asserting the right of the individual to approach God through the mediation of Christ only instead of through that of priests: the individual, as an inevitable consequence, claiming the right of private judgement in matters religious instead of bowing to dogma based on the authority of the Church from ages past. These conclusions Erasmus abhorred. He was all for reform, but a violent severance with the past seemed to him a monstrous remedy. He always exercised, though he did not always claim, the right of thinking for himself; but he would never have dreamed of allowing the same freedom to the ignorant or the unlearned. The aim of his life was to increase knowledge, in the assurance that from that reform would surely come; but to force on reform by an appeal to passion, to settle religious difficulties by an appeal to emotion was to him madness. The ideals of Erasmus and Luther were irreconcilable: and bitterness soon arose between them. From both sides Erasmus was assailed with unmeasured virulence. The strict Catholics called him a heretic, the Lutherans a coward. But throughout these stormy years he never wavered. At the end he was still pursuing the ideal which he had sought at the outset of his public career--reform guided by knowledge. He lived to see some of the disasters which he had dreaded as the result of encouragement given to lawless passion--the Peasants' Revolt in 1525, and the Anabaptist horrors at Munster ten years later. If he could have foreseen the course of the next century, he would not have lacked instances with which to enforce his moral.