On the route from Worms Luther was taken prisoner by soldiers of the Elector, Frederick of Saxony, according to arrangements that had been made for his protection, and was brought to the castle at Wartburg where he remained for close on a year (May 1521-March 1522) under the assumed name of Yonker George, safe in spite of the imperial decrees. In the silence of his retreat at Wartburg Luther had an opportunity for reflection on the gravity of the situation that he had created. At times he trembled, as he thought of separating himself definitely from the great world-wide organisation which recognised the jurisdiction of the Bishop of Rome, and of setting up his own judgment against the faith that had been handed down for centuries, and that was supported by the ablest scholars from the days of Clement of Rome to those of St. Thomas and St. Bonaventure. In his anxiety of mind he was the victim of hallucinations, believing that the spirit of evil appeared to him in visible form, and held commune with him in human speech. He was assailed, too, with violent temptations of the flesh, which reduced him to a state bordering on despair. But these moments of depression passed away, to be succeeded by fits of wild exultation in which he rejoiced at the storm that he had created already, and at the still greater storm he was soon to create. He set to work with tireless energy, believing himself to be inspired from on high as was the apostle, St. John, during his stay in the island of Patmos. At the instigation of his friends, who urged him to attack the celibacy of the monks and nuns, he turned his attention to this question, and issued a work /On Monastic Vows/, in which he declared that such vows of chastity, being opposed to the freedom of the Gospel, were sinful and should be neglected. In his book /On the Mass/ he assailed the Mass and the whole theory of the Christian priesthood, declaring that every believer was in a true sense a priest. He poured out a most violent torrent of abuse against Henry VIII. of England, who, in his /Defence of the Seven Sacraments/, had ventured to join issue with the German reformer. At the same time he undertook to prepare a translation of the New Testament as a means of advancing his propaganda. By aid of mis-translations and marginal notes he sought to popularise his views on Faith and Justification, and to win favour with the people by opening to them the word of God, which he asserted falsely had been closed against them for centuries.