Deuteronomy 20:13

New Revised Standard Version Catholic Interconfessional

and when the Lord your God gives it into your hand, you shall put all its males to the sword.

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The Lord says to my lord, “Sit at my right hand until I make your enemies your footstool.”

But as for these enemies of mine who did not want me to be king over them—bring them here and slaughter them in my presence.’ ”

If it does not submit to you peacefully, but makes war against you, then you shall besiege it;