The unchaste, then, say that sins contrary to purity are but a small evil. Like "the sow . . . wallowing in the mire" (2Peter 2:22), they are immersed in their own filth, so that they do not see the malice of their actions; and therefore they neither feel nor abhor the stench of their impurities, which excite disgust and horror in all others. Can you, who say that the vice of impurity is but a small evil - can you, I ask, deny that it is a mortal sin? If you deny it, you are a heretic; for as Saint Paul says, "Do not err: neither fornicators, nor idolaters, nor adulterers, nor the effeminate, nor liers with mankind, nor thieves, nor covetous, nor drunkards, nor railers, nor extortioners, shall possess the kingdom of God" - 1Corinthians 9-10. It is a mortal sin; it cannot be a small evil. It is more sinful than theft, or detraction, or the violation of the fast. How then can you say that it is not a great evil? Perhaps mortal sin appears to you to be a small evil? Is it a small evil to despise the grace of God, to turn your back on Him, and to lose His friendship, for a transitory, beastly pleasure?
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