Knox's powers as a preacher came to the attention of the chaplain of the garrison, John Rough. While Rough was preaching in the parish church on the Protestant principle of the popular election of a pastor, he proposed Knox to the congregation for that office. Knox did not relish the idea. According to his own account, he burst into tears and fled to his room. Within a week, however, he was giving his first sermon to a congregation that included his old teacher, John Major. He expounded on the seventh chapter of the Book of Daniel, comparing the Pope with the Antichrist. His sermon was marked by his consideration of the Bible as his sole authority and the doctrine of justification by faith alone, two elements that would remain in his thoughts throughout the rest of his life. A few days later, a debate was staged that allowed him to lay down additional theses including the rejection of the Mass, Purgatory, and prayers for the dead.