He felt himself already strong and secure in his faith: in 1506 he wrote to Spalatinus, who was the connecting link between him and the Elector, Frederic the Wise, that the Elector was of all men most knowing in secular wisdom, but in things pertaining to God and the salvation of souls, he was struck with sevenfold blindness. Luther had reason for the opinion here expressed, for the domestic disposition of this sober-minded prince showed itself in his anxiety to provide for his home the means of grace bestowed by the old Church. Amongst other things he had a particular fancy for relics, and Staupitz, vicar-general of the Augustine monks in Germany, was at that time engaged in collecting these treasures for the Elector. This absence of his superior was very important to Luther, for he had to fill his place. He was already a man of high repute in his order; but though a professor at Wittenberg, he continued to reside in his monastery, and generally wore his monk's dress. He visited the thirty monasteries of his congregation, deposed priors, delivered strong rebukes on account of lax discipline, severely admonished criminal monks, and had become in 1517 a man of fully developed character and commanding powers; yet he still preserved somewhat of the trusting simplicity of the monastic brother. Thus, when he had affixed the Theses against Tetzel to the church door, he writes confidingly to the Archbishop Albrecht of Maintz, the protector of the trader in indulgences. Full of the popular faith in the good sense and the good will of the governing powers, Luther thought--he often said so later--nothing was necessary but to represent straightforwardly to the princes of the Church the injurious effects and immorality of these malpractices.[27] But how childish did this zeal of the monk appear to the smooth and worldly prince of the Church! That which had roused such deep indignation in the upright man, had from the archbishop's point of view long been a settled question. The sale of indulgences was a much lamented evil in the Church, but unavoidable, as are to politicians many regulations not good in themselves, but necessary to preserve some great interests. The greatest interest of the archbishops and the guardians of the Romish Church was their dominion, which was to be won and maintained by such means of acquiring money. The greatest interest of Luther and the people was truth; here, therefore, their paths separated.