Exodus 20:14 - Coke's Commentary on the Holy Bible

Thou shalt not commit adultery— After securing the life, the Lord proceeds to secure that part of property which is often as dear, or dearer to human creatures, than life itself. The Hebrew word here used ףּתנא tinap, plainly shews that the prohibition in this commandment primarily refers to that act of uncleanness known by the name of adultery. Μοιχεια also, in the Greek, implies the same. Here again, as on the former commandment, we refer to Matthew 5:27; Matthew 5:48 where it appears, that what we have observed on the word is just, and where we shall find the law drawn out to its full spiritual extent. See Leviticus 20:10 where death is denounced as the punishment of adultery; a punishment not peculiar to the Jewish law: it was inflicted on the adulterer by the laws of several heathen nations.