“Lust is an inordinate desire of unlawful pleasures. It is a vice most widely spread in the world; one that is most violent in its attacks, most insatiable in its cravings. Hence St. Augustine says that the severest warfare which a Christian has to maintain is that in defense of chastity, for such combats are frequent, and victories rare.”
Venerable Louis of Granada, OP, The Sinner’s Guide, Chapter 32