1 Kings 20:42

He said to him, “Thus says the Lord, ‘Because you have let go out of your hand the man whom I had devoted to destruction, therefore your life shall go for his life, and your people for his people.’”

1 Kings 22:31-37

Now the king of Aram had commanded the thirty-two captains of his chariots, saying, “Do not fight with small or great, but with the king of Israel alone.”

1 Kings 20:39

As the king passed by, he cried to the king and said, “Your servant went out into the midst of the battle; and behold, a man turned aside and brought a man to me and said, ‘Guard this man; if for any reason he is missing, then your life shall be for his life, or else you shall pay a talent of silver.’

1 Samuel 15:9-11

But Saul and the people spared Agag and the best of the sheep, the oxen, the fatlings, the lambs, and all that was good, and were not willing to destroy them utterly; but everything despised and worthless, that they utterly destroyed.

1 Kings 20:34

Ben-hadad said to him, “The cities which my father took from your father I will restore, and you shall make streets for yourself in Damascus, as my father made in Samaria.” Ahab said, “And I will let you go with this covenant.” So he made a covenant with him and let him go.

2 Kings 6:24

Now it came about after this, that Ben-hadad king of Aram gathered all his army and went up and besieged Samaria.

2 Kings 8:12

Hazael said, “Why does my lord weep?” Then he answered, “Because I know the evil that you will do to the sons of Israel: their strongholds you will set on fire, and their young men you will kill with the sword, and their little ones you will dash in pieces, and their women with child you will rip up.”

2 Chronicles 18:33-34

A certain man drew his bow at random and struck the king of Israel in a joint of the armor. So he said to the driver of the chariot, “Turn around and take me out of the fight, for I am severely 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
Ben-hadad said to him, “The cities which my father took from your father I will restore, and you shall make streets for yourself in Damascus, as my father made in Samaria.” Ahab said, “And I will let you go with this covenant.” So he made a covenant with him and let him go.
1 Kings 22:31
Now the king of Aram had commanded the thirty-two captains of his chariots, saying, “Do not fight with small or great, but with the king of Israel alone.”
1 Samuel 15:9
But Saul and the people spared Agag and the best of the sheep, the oxen, the fatlings, the lambs, and all that was good, and were not willing to destroy them utterly; but everything despised and worthless, that they utterly destroyed.

Thy life shall go

1 Kings 22:31
Now the king of Aram had commanded the thirty-two captains of his chariots, saying, “Do not fight with small or great, but with the king of Israel alone.”
2 Kings 6:24
Now it came about after this, that Ben-hadad king of Aram gathered all his army and went up and besieged Samaria.
2 Kings 8:12
Hazael said, “Why does my lord weep?” Then he answered, “Because I know the evil that you will do to the sons of Israel: their strongholds you will set on fire, and their young men you will kill with the sword, and their little ones you will dash in pieces, and their women with child you will rip up.”
2 Chronicles 18:33
A certain man drew his bow at random and struck the king of Israel in a joint of the armor. So he said to the driver of the chariot, “Turn around and take me out of the fight, for I am severely wounded.”