The seventh commandment is about more than not cheating

"You shall not commit adultery," (Exodus 20:14) is the seventh commandment God gives to Moses at Mt. Sinai. This commandment prohibits the act of sex by a married person with anyone other than their spouse. The adultery addressed in this commandment is different than the act of fornication, which is defined as sex between single people and also prohibited by God. The seventh commandment refers to adultery as it relates to married couples.

By stating this command so clearly, God forces his followers to face the fact that...

Read More Here.