Note:
C.S. Lewis writes about three reasons it is really hard to be fully chaste. If he were writing now, I wonder whether he would especially emphasize the first reason: the overwhelming presence of salacious images and text washing onto our screens. Anyway, the fact that he lists “the contemporary propaganda for lust” first is, in a way, a bit of a comfort in that it might tell us that we are not any more tempted than people nearly 100 years ago were.

Quote:
“[T]here are three reasons why it is now specially difficult for us to desire — let alone achieve — complete chastity. In the first place our warped natures, the devils who tempt us, and all the contemporary propaganda for lust, combine to make us feel that the desires we are resisting are so ‘natural,’ so ‘healthy,’ and so reasonable, that it is almost perverse and abnormal to resist them. … In the second place, many people are deterred from seriously attempting Christian chastity because they think (before trying) that it is impossible. … Thirdly, people often misunderstand what psychology teaches about ‘repressions.’ It teaches us that ‘repressed’ sex is dangerous. But ‘repressed’ is here a technical term: it does not mean ‘suppressed’ in the sense of ‘denied’ or ‘resisted.’ … [T]hose who are seriously attempting chastity are more conscious, and soon know a great deal more about their own sexuality than anyone else.” (p. 92-94)

Source: Lewis, C.S. Mere Christianity. New York: Macmillan, 1960.