Here comes in that whole sea of laws and impossible questions about "cases of sin," [6] etc., since it is impossible for a man to know when he has in his heart committed the mortal sins of pride, lust, or envy. Nay, how can the priest know this, when he is set in judgment upon mortal sins alone? Can he know another's heart who does not thoroughly know his own? Hence it comes that many people confess many things, not knowing whether they are sins or not; and to this they are driven by that sentence of Gregory, "A good mind will confess guilt even where there is no guilt." They [i. e., the priests] wish that what is offered to God shall be offered to themselves—so immense is the arrogance of priests and pontiffs, and so haughty the pride of the Pharisees—and they do not see, meanwhile, that if this offering were made to man, the whole of life would be nothing else than confession, and that even this confession would have to be confessed in another confession by the man who fears guilt where there is no guilt, since even good works are not without guilt, and Job is afraid of all his works. [Job 9:28] SEVENTH [Sidenote: Hidden Sins—What Hidden Sins Should be Confessed?] Let some one else, then, explain this. I am content with this, that not all the sins of the heart are to be confessed. But if some are to be confessed, I say that it is only those which a man clearly knows that he has purposed in his heart against the commandments of God;[7] not, therefore, mere thoughts about a virgin or a woman, nor, on the other hand, the thoughts of a woman about a youth, nor the affections or ardor of lust, that is to say, the inclinations of the one sex toward the other, however unseemly, nor, I would add, even passions of this sort; for these thoughts are frequently passions inspired by the flesh, the world, or the devil, which the soul is compelled unwillingly to bear, sometimes for a long while, even for a whole day, or a week; as the apostle Paul confesses of his thorn in the flesh. [2 Cor. 12:7] The consequence of all this is that a purpose to avoid these things is impossible and vain and deceitful, for the inclinations and desires of the sexes for one another do not cease so long as occasion is given them, and the devil is not quiet, and out whole nature is sin. But those who wish to be without sin and who believe that man is sound and whole, erect these crosses for us that we may not cease to confess (even to the priest) what things soever tickle us never so little. Therefore, if these hidden things of the heart ought to be confessed at all, only those things should be confessed which involve full consent to the deed; and such things happen very rarely or never to those who wish to lead pious lives, even though they are constantly harassed by desires and passions. EIGHT [Sidenote: Mortal and Venial Sins]