Luther was, it should be remembered, thoroughly in accord with Pope and with Emperor in the belief that it was the duty of the believers to stamp out heresy. He only differed with them as to what constituted heresy. In 1525, we find him invoking the aid of the censorship regulations of Saxony and of Brandenburg for the purpose of stamping out the “pernicious doctrines” of the Anabaptists and of the followers of Zwingli. The Protestant princes were, for the most part, more than willing to establish and to maintain a censorship for the presses of their several localities, as such a system served in more ways than one to strengthen their authority, while it could be utilised also to head off undesirable criticism. As an evidence of the very general distribution secured for Luther’s writings, may be cited a letter, dated February 14, 1519, written to the Reformer from Basel by the publisher Froben, in which he speaks of large supplies of the Basel editions being called for, not only in Germany, but in France, Spain, Italy, Brabant, and England. The reference is to the first collection of Luther’s works, of which impressions were printed in 1518, 1519, and again in 1520.[128] Kapp is of opinion that from these sales the author asked for and received no return either in the form of royalty or honorarium. His purposes were accomplished when his teachings, correctly printed, in editions authorised and supervised by himself, and sold at the lowest prices compatible with accurate typography, had secured the widest possible circulation. While, therefore, Luther serves as an example of a successful author, the most successful, in fact, that the world had as yet seen, his experience as an author did not help to advance the recognition of the rights of an author in his literary productions. To Luther, his writings were not property, to be controlled for the benefit of the author, but great truths and sound doctrine essential for the saving of souls, and to be scattered widely for the benefit of the reader. Köpflin, writing to Luther from Hagenau in 1519, says, “We have printed your books one after another, and within six months have disposed of all the copies.”