In spite of all obstacles, Tetzel preached the indulgence with signal success at Leipsic, Magdeburg, Halberstadt, Berlin, and other places. At length, about the end of October. 1517, he arrived at Yüterbock, near Wittenberg, just at the time for gaining the special indulgence of All Saints. In vain the Augustinians secretly did what they could to prevent the people from flocking to hear him. The very students of the new Wittenberg university, expressly founded as it was as a rival to that of Leipsic, deserted the lecture-halls in such numbers that the professors were filled with alarm and indignation. In particular, Dr. Martin Luther was exasperated to find himself so completely eclipsed by the proximity of Tetzel, against whom he fruitlessly inveighed in the temporary church of the Augustinian hermits. Even his own penitents, regardless of his admonitions and refusals of absolution, forsook his confessional to obtain the indulgence proclaimed at Yüterbock. All at once they seemed to forget the maxims he had taken so much pains to instil into their minds respecting divine grace and good works! Long had he waited for an opportunity to broach his new doctrine openly, and he and his disciples resolved that now or never was the time to do so.
Accordingly, on the 31st of October Luther posted up his famous ninety-five theses at the door of All Saints' church in Wittenberg, and challenged all the world to dispute with him on the doctrine they maintained. Ostensibly they were levelled against the alleged abuses of the papal indulgence. But attacks on the doctrine itself, as well as on the authority of the pope, were insidiously intermingled with them.
"Not the affair of the indulgence, not Tetzel, not the corruption and ignorance of the clergy, not the decay of discipline," says Dr. Gröne, "but the circumstance that Luther, previous to the posting up of his theses, was a heretic, and found support in the Elector Frederic—this it was that gave rise to the great schism in the church."
Dr. Gröne substantiates his assertion by authenticated facts, and a critical examination of Luther's ninety-five theses, which, says he,
"Were the point of transition from secret to open from timid to obstinate, heresy. They were the seed which, sown in the soil, contains, not only virtually, but really, all that, as germ and plant, it has a right to contain. They were the result, the production of Luther's mental life, corroded, as it was, by error and learned self-conceit; they were as intimately united with it as the stem is with the root, therefore they could only be abandoned in case the author himself transformed his entire interior life. Hence, too, is to be derived the obstinacy with which Luther clung to them, with which he would still have clung to them, even if they had not earned him general applause; hence the circumstance that, in defending them, he involved himself deeper and deeper in heresy."
By means of the press Luther's theses were soon spread all over Germany. Tetzel, seeing the riotous applause they met with from the enemies of the church generally, and from his own enemies in particular, suspended his preaching; and, with the concurrence of the archbishop of Mentz, repaired for advice to his former preceptor, Dr. Conrad Wimpina, at that time rector of the university of Frankfort-on-the-Oder. Wimpina advised him to answer Luther's challenge with a series of antitheses. Tetzel did so, and published against Luther's ninety-five theses a hundred and six antitheses. They obtained for him the degree of doctor of divinity. In the clearest manner they set forth the true Catholic doctrine of the absolute necessity of repentance, confession, and satisfaction for the pardon of sin, affirming that, though an indulgence exempts the sinner from the vindicatory penalties of the church, it leaves him just as much bound as ever to submit to her medicinal and preservative ones; that it does not derogate from the merits of Christ, since its whole efficacy is due to the atoning passion of Christ; as also that the pope has power only by means of suffrage to apply the benefits of an indulgence to the souls in purgatory. Moreover, to say the pope cannot absolve the least venial sin is erroneous; and equally so to deny that all vicars of Christ have the same power as Peter had: rather to assert that Peter, in the matter of indulgences, had more power than they, is both heretical and blasphemous. One of the many slanders on Tetzel is, that he was not the author of the antitheses that he published, but that Dr. Wimpina wrote them for him. Luther himself flung this taunt in his face, and so gave it the prestige among his party of an undoubted fact. Dr. Gröne enters fully into the case, and terminates his inquiry with "venturing to believe that, by his vindication, he has annihilated every substantial ground for doubting that Tetzel was the real author of the antitheses in question." They did not, of course, silence Luther, who replied to them with a popular compendium in German of his ninety-five theses in twenty articles. Tetzel rejoined with twenty others, also in German. In the nineteenth he declares of Luther's doctrine, in the tone of a prophet, that, in consequence of it, "many people will contemn the authority and power of his holiness the pope and the Roman see, will intermit the works of sacramental satisfaction, will no longer believe their pastors and teachers, but will explain, every one for himself, the sacred Scriptures according to private fancy and whim, and believe just what every one chooses, to the great detriment of souls throughout Christendom."
At a time when all the most learned men in Germany regarded the matter as nothing but a scholastic dispute, when many even in Rome deemed it a mere monkish quarrel, Tetzel, by thus pointing out in such clear and concise terms what Luther's principles really involved, what fatal results they would produce, evinced, in Dr. Gröne's opinion, a more than ordinary penetration of mind.
Luther's fundamental thought in attacking indulgences was this: That indulgences are not of faith, because not taught in the Bible, not taught by Christ and his apostles; they emanate, he said, only from the pope. Now, if this thought was an erroneous one, if the pope in questions of faith and morals is infallible, if he alone possesses the right to decide the true sense and meaning of Scripture, every Catholic is bound on all such questions to submit to him; and Luther, if he persisted in maintaining his doctrine, passed sentence on himself as an apostate and a heretic, cut himself off from all escape, and had no other choice left than that of either being punished as a heretic, or making a recantation. Hence, in order to drive him from the field, it was requisite to prove that, besides the truths explicitly declared in holy writ, there are other truths in the church which we are equally bound to believe; and that they comprise all those doctrines relating to faith which are defined as such by the holy see. By setting up those propositions the dispute would be raised to one of principle, and Luther would be compelled to speak out on the pope's authority in matters of faith and practice.
These considerations spurred Tetzel on to issue against Luther's fifty theses on the power of the pope; for, indeed, it had not eluded his observation that much the greater part of the applause received by Luther was owing far more to his insidious attacks on the authority of the holy see than to his reprobation of the indulgence. Tetzel's fifty theses, published about the end of April, 1518, maintained, therefore, that the highest power having been received by the pope exclusively from God, cannot be extended or limited, either by any man or by the whole world, but only by God alone. That in his power of jurisdiction the pope stands above all other bishops separate or united. That, although, as a private man, the pope may hold, on a point of faith, a wrong opinion, yet, when he pronounces judgment on it ex cathedrâ, he is infallible. That indulgences cannot be granted by the rest of the prelates, whether collectively or singly, but only by the "Bridegroom of the whole church," namely, the pope. That what is true and of faith about indulgences, only the pope can decide. That the church has many Catholic truths, which are neither expressly declared in the canon of Scripture, nor explicitly stated by the holy fathers. That all doctrines relating to faith, and defined as such by the apostolic see, are to be reckoned among Catholic truths, whether or not they are contained in the Bible. As a warning for the elector of Saxony, Tetzel declares that all those who patronize heretics, and use their power to prevent them from being put upon their trial before the lawful judge, incur excommunication.