1 Samuel 24:18-20

18You have declared today the good that you have done to me, for when the Lord put me into your hand, you did not kill me.

19For if a man finds his enemy, will he let him go away unharmed? So may the Lord reward you with good in return for what you have done for me this day.

20Now, behold, I know that you will certainly be king and that the kingdom of Israel will be established in your hand.