Deuteronomy 7:2-3

2 aand when the Lord your God gives them over to you, and you defeat them, then you must bdevote them to complete destruction.
That is, set apart ( devote) as an offering to the Lord (for destruction)
dYou shall make no covenant with them and show no mercy to them.
3 eYou shall not intermarry with them, giving your daughters to their sons or taking their daughters for your sons,

Joshua 23:12-13

12For if you turn back and cling to the remnant of these nations remaining among you fand make marriages with them, so that you associate with them and they with you, 13know for certain that gthe Lord your God will no longer drive out these nations before you, hbut they shall be a snare and a trap for you, a whip on your sides and thorns in your eyes, until you perish from off this good ground that the Lord your God has given you.

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