1 Samuel 18:17-18

17Then Saul said to David, “Here’s my oldest daughter, Merab. I want to give her to you in marriage. Only be a brave warrior for me and fight the battles of the Lord.” For Saul thought, “There’s no need for me to raise my hand against him. Let it be the hand of the Philistines!”

18David said to Saul, “Who am I? Who are my relatives or the clan of my father in Israel that I should become the king’s son-in-law?”