1 Samuel 18:17-18

17Finally, Saul said to David, “Here is my oldest daughter Merab. I will give her to you as your wife if you prove yourself to be a warrior for me and fight the Lord’s battles.” (Saul thought, “I must not lay a hand on him. Let the Philistines do that.”)

18“Who am I?” David asked Saul. “And how important are my relatives or my father’s family in Israel that I should be the king’s son-in-law?”