John Gill Commentary Exodus 20:14

"Thou shalt not commit adultery." — Exodus 20:14 (ASV)

Thou shall not commit adultery ,
] Which, strictly speaking, is only that sin which is committed with another man's wife, as Jarchi observes; but Aben Ezra thinks the word here used signifies the same as another more commonly used for whoredom and fornication; and no doubt but fornication is here included, which, though it was not reckoned a crime among some Heathens, is within the reach of this law, and forbidden by it, it being an impure action, and against a man's body, as the apostle says, (1 Corinthians 6:18)

as well as sins of a more enormous kind, as unnatural lusts and copulations, such as incest, sodomy, bestiality, &c. and even all unchaste thoughts, desires, and affections, obscene words, and impure motions and gestures of the body, and whatever is in itself unclean or tends to uncleanness;

as it also requires that we should, as much as in us lies, do all we can to preserve our chastity, and the chastity of others, pure and inviolate, see (Matthew 5:28) , this is the seventh commandment.