Deuteronomy 20:13

Revised Standard Version (RSV-CI)

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, till I make your enemies your footstool.”

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

But if it makes no peace with you, but makes war against you, then you shall besiege it;