The Leipzig University professor, in his indignation, refers Luther to the warning he himself (in his sermons on the Ten Commandments) had given against manners of talking and acting which tempt to impurity; he continues: “And now you set aside every feeling of shame, you speak and write of questionable subjects in such a disgraceful fashion that decent men, whether married or unmarried, cover their faces and fling away your writings with execration. In order to cast dishonour upon the brides of Christ you [in your writings], so to speak, lead unchaste men to their couches, using words which for very shame I cannot repeat.” He also answers his opponent’s constant objection that without marriage, on account of the impulse of nature, people must needs be ever falling into sin. “You forget two things, viz. that grace is stronger than nature and that, as Augustine rightly teaches, no one sins without free consent. You exaggerate that impulse and speak of ‘sin’ merely to exonerate your own behaviour and your doctrine. In other matters you declare that everything is possible to him who believes. You, like all other Catholics, were formerly convinced that involuntary movements of the flesh are not sinful unless a man consents to them; they are to the good a cross rather than a fault, and frequently only come from the devil and are not imputed to them at all.”[370] This protest from Leipzig was reinforced in 1523 from Ingolstadt by Dr. Johann Eck, who kept a keen eye on Luther and pursued him with a sharp pen. In the following description of Luther his bitter opponent complains not only of the frivolous behaviour of the apostate monk in his former monastery which the Elector had made over to him, but above all of the untruth and dishonesty displayed in his writings. “More than once have I proved,” he says, “that he is a liar and hence that he has for his father, him [the devil] of whom the Scripture says that he is a liar and a murderer.” “The fellow exudes lies from every pore and is inconstancy itself (_homo totus mendaciis scatens nil constat_). His teaching too is full of deception and calumny. What he has just advanced, he presently rejects without the least difficulty.” “The dregs of those vices of which he is always accusing the Christians, we rightly pour back upon his own head; let him drink himself of the cup he has mixed.” “He heaps up a mountain of evil on the Pope and the Church,” but with “his nun,”--this is what he adds in a later edition in his indignation with Luther’s marriage--“he is really worshipping Asmodeus”; and this he is not ashamed to do in the old monastery of the Augustinians, “where once pious monks served the Lord God, and pious foundations, now alienated from their original purpose, proclaimed the Christian virtues to the faithful.”[371]