1 Samuel 24:17-21

17And he said to David, “You are a better man than I am, for you have repaid me good for evil.

18Yes, you have been amazingly kind to me today, for when the Lord put me in a place where you could have killed me, you didn’t do it.

19Who else would let his enemy get away when he had him in his power? May the Lord reward you well for the kindness you have shown me today.

20And now I realize that you are surely going to be king, and that the kingdom of Israel will flourish under your rule.

21Now swear to me by the Lord that when that happens you will not kill my family and destroy my line of descendants!”