Deuteronomy 20:13

New Century Version

The Lord your God will give it to you. Then kill all the men with your swords,

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The Lord said to my Lord, “Sit by me at my right side until I put your enemies under your control.”

Now where are my enemies who didn’t want me to be king? Bring them here and kill them before me.’ ”

But if they do not make peace with you and fight you in battle, you should surround that city.