Deuteronomy 24:4
her first husband who divorced her is not permitted to remarry her after she has become ritually impure, for that is offensive to the Lord. You must not bring guilt on the land which the Lord your God is giving you as an inheritance.
Jeremiah 3:1
"If a man divorces his wife and she leaves him and becomes another man's wife, he may not take her back again. Doing that would utterly defile the land. But you, Israel, have given yourself as a prostitute to many gods. So what makes you think you can return to me?" says the Lord.
Leviticus 18:24-28
"'Do not defile yourselves with any of these things, for the nations which I am about to drive out before you have been defiled with all these things.
Joshua 22:17-18
The sin we committed at Peor was bad enough. To this very day we have not purified ourselves; it even brought a plague on the community of the Lord.