1 Kings 20:42

He said to him: These are the words of Jehovah: 'Because you have let go from your hands the man whom I had put to the curse, your life will be taken for his life, and your people for his people.'

1 Kings 22:31-37

Now the king of Aram had given orders to the thirty-two captains of his war-carriages, saying: Make no attack on small or great, but only on the king of Israel.

1 Kings 20:39

When the king went by he cried out to him: Your servant went out into the fight. A man came to me. He brought a man to me and said: 'guard this man. Do not let him get away. Your life is the price of his life or you will have to give a talent of silver in payment.'

1 Samuel 15:9-11

Saul and his men spared Agag's life and did not kill the best sheep and cattle, the best calves and lambs, or anything else that was good. They destroyed only what was useless or worthless.

1 Kings 20:34

Benhadad said: The towns my father took from your father I will give back. You may name streets for yourself in Damascus as my father did in Samaria. As for me, at the price of this agreement you will let me go. So he made an agreement with him and let him go.

2 Kings 6:24

After that King Benhadad of Syria led his entire army against Israel in siege of the city of Samaria.

2 Kings 8:12

Why are you crying? Hazael asked. Because I know the horrible things you will do against the people of Israel, Elisha answered. You will burn their fortresses, slaughter their finest young men, batter their children to death, and rip open their pregnant women.

2 Chronicles 18:33-34

One man aimed his bow at random and hit the king of Israel between his scale armor and his breastplate. Ahab told the chariot driver: Turn around, and get me away from these troops for I am badly wounded.

Treasury of Scripture Knowledge

Summary

And he said unto him, Thus saith the LORD, Because thou hast let go out of thy hand a man whom I appointed to utter destruction, therefore thy life shall go for his life, and thy people for his people.

Bible References

Because

1 Kings 20:34
Benhadad said: The towns my father took from your father I will give back. You may name streets for yourself in Damascus as my father did in Samaria. As for me, at the price of this agreement you will let me go. So he made an agreement with him and let him go.
1 Kings 22:31
Now the king of Aram had given orders to the thirty-two captains of his war-carriages, saying: Make no attack on small or great, but only on the king of Israel.
1 Samuel 15:9
Saul and his men spared Agag's life and did not kill the best sheep and cattle, the best calves and lambs, or anything else that was good. They destroyed only what was useless or worthless.

Thy life shall go

1 Kings 22:31
Now the king of Aram had given orders to the thirty-two captains of his war-carriages, saying: Make no attack on small or great, but only on the king of Israel.
2 Kings 6:24
After that King Benhadad of Syria led his entire army against Israel in siege of the city of Samaria.
2 Kings 8:12
Why are you crying? Hazael asked. Because I know the horrible things you will do against the people of Israel, Elisha answered. You will burn their fortresses, slaughter their finest young men, batter their children to death, and rip open their pregnant women.
2 Chronicles 18:33
One man aimed his bow at random and hit the king of Israel between his scale armor and his breastplate. Ahab told the chariot driver: Turn around, and get me away from these troops for I am badly wounded.