Lust is the love of the pleasures that are contrary to purity.
No sins, my children, ruin and destroy a soul so quickly as this shameful sin; it snatches us out of the hands of the good God and hurls us like a stone into an abyss of mire and corruption. Once plunged in this mire, we cannot get out, we make a deeper hole in it every day, we sink lower and lower. Then we lose the faith, we laugh at the truths of religion, we no longer see Heaven, we do not fear Hell. O my children! how much are they to be pitied who give way to this passion! How wretched they are! Their soul, which was so beautiful, which attracted the eyes of the good God, over which He leant as one leans over a perfumed rose, has become like a rotten carcass, of which the pestilential door rises even to His throne. . . .
See, my children! Jesus Christ endured patiently, among His Apostles, men who were proud, ambitious, greedy--even one who betrayed Him; but He could not bear the least stain of impurity in any of them; it is of all vices that which He has most in abhorrence: "My Spirit does not dwell in you," the Lord says, "if you are nothing but flesh and corruption. " God gives up the impure to all the wicked inclinations of his heart. He lets him wallow, like the vile swine, in the mire, and does not even let him smell its offensive exhalations. . . . The immodest man is odious to everyone, and is not aware of it. God has set the mark of ignominy on his forehead, and he is not ashamed; he has a face of brass and a heart of bronze; it is in vain you talk to him of honour, of virtue; he is full of arrogance and pride. The eternal truths, death, judgment, Paradise, Hell-nothing terrifies him, nothing can move him. So, my children, of all sins, that of impurity is the most difficult to eradicate. Other sins forge for us chains of iron, but this one makes them of bull's hide, which can be neither broken nor rent; it is a fire, a furnace, which consumes even to the most advanced old age. See those two infamous old men who attempted the purity of the chaste Susannah; they had kept the fire of their youth even till they were decrepit. When the body is worn out with debauchery, when they can no longer satisfy their passions, they supply the place of it, oh, sham! by infamous desires and memories.
With one foot in the grave, they still speak the language of passion, till their last breath; they die as they have lived, impenitent; for what penance can be done by the impure, what sacrifice can be imposed on himself at his death, who during his life has always given way to his passions? Can one at the last moment expect a good confession, a good Communion, from him who has concealed one of these shameful sins, perhaps, from his earliest youth--who has heaped sacrilege on sacrilege? Will the tongue, which has been silent up to this day, be unloosed at the last moment? No, no, my children; God has abandoned him; many sheets of lead already weigh upon him; he will add another, and it will be the last . . .