causes at work during the Middle Ages to render rational liberty eventually possible with advancing civilization. Looking therefore upon the church as an instrumentality to effect certain beneficent results in the course of human improvement, we may regard celibacy as a necessary element of sacerdotalism, the abolition of which would have required the entire destruction of the papal system and the fundamental reconstruction of ecclesiastical institutions. What we may now readily discern to have been a means, to Gregory, however, was an end, and to the enforcement of celibacy as necessary to that object he devoted himself with unrelenting vigor. The belief that he was appointed of God, and set apart for the task of cleansing the church of the Nicolitan heresy which had defied his predecessors is well illustrated by the contemporary legend of some pious Pisans, who, spending the night before his election in prayer in the basilica of St. Peter, saw that holy saint himself traverse the church accompanied by Hildebrand, whom he commanded to gather some droppings of mares with which the sacred edifice was defiled, to place them in a sack, and to carry them out on his shoulders.[534] The severe austerity of his virtue, moreover, was displayed by his admirers in the story that once, when dangerously ill, his niece came to inquire as to his health. To relieve her anxiety he played with her necklace, and jestingly asked if she wished to be married; but on his recovery he found that he could no longer weep with due contrition over his sins, and that he had lost the grace of repentance. He long and vainly searched for the cause, and finally entreated his friends to pray for him, when the Virgin appeared to one of them, and sent word to Gregory that he had fallen from grace in consequence of the infraction of his vows committed in touching the necklace of his niece.[535] * * * * *