He was suddenly compelled to flee from Paris. The theologians of the Sorbonne were vehemently opposed to the "royal lecturers" who represented the Humanism favoured by Margaret, the sister of Francis, and Queen of Navarre. In their wrath they had dared to attack Margaret's famous book, _Miroir de l'âme pécheresse_, and had in consequence displeased the Court. Nicolas Cop, the friend of Calvin, professor in the College of Sainte Barbe, was Rector of the University (1533). He assembled the four faculties, and the faculty of medicine disowned the proceedings of the theologians. It was the custom for the Rector to deliver an address before the University yearly during his term of office, and Cop asked his friend Calvin to compose the oration.[107] Calvin made use of the occasion to write on "Christian Philosophy," taking for his motto, "_Blessed are the poor in spirit_" (Matt. v. 3). The discourse was an eloquent defence of Evangelical truth, in which the author borrowed from Erasmus and from Luther, besides adding characteristic ideas of his own. The wrath of the Sorbonne may be imagined. Two monks were employed to accuse the author of heresy before _Parlement_, which responded willingly. It called the attention of the King to papal Bulls against the Lutheran heresy. Meanwhile people discovered that Calvin was the real author, and he had to flee from Paris. After wanderings throughout France he found refuge in Basel (1535). It was there that he finished his _Christianæ Religionis Institutio_, which had for its preface the celebrated letter addressed to Francis I. King of France. The book was the strongest weapon Protestantism had yet forged against the Papacy, and the letter "a bold proclamation, solemnly made by a young man of six-and-twenty, who, more or less unconsciously, assumed the command of Protestantism against its enemies, calumniators, and persecutors." News had reached Basel that Francis, who was seeking the alliance of the German Lutheran Princes, and was posing as protector of the German Protestants, had resolved to purge his kingdom of the so-called heresy, and was persecuting his Protestant subjects. This double-dealing gave vigour to Calvin's pen. He says in his preface that he wrote the book with two distinct purposes. He meant it to prepare and qualify students of theology for reading the divine Word, that they may have an easy introduction to it, and be able to proceed in it without obstruction. He also meant it to be a vindication of the teaching of the Reformers against the calumnies of their enemies, who had urged the King of France to persecute them and drive them from France. His dedication was: _To His Most Gracious Majesty, Francis, King of France and his sovereign, John Calvin wisheth peace and salvation in Christ._ Among other things he said: