Deuteronomy 20:13

New King James Version

And when the Lord your God delivers it into your hands, you shall strike every male in it with the edge of the sword.

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But bring here those enemies of mine, who did not want me to reign over them, and slay them before me.’ ”

The Lord said to my Lord, “Sit at My right hand, Till I make Your enemies Your footstool.”

Now if the city will not make peace with you, but makes war against you, then you shall besiege it.