1 Samuel 18:17-21

17And Saul said to David, Behold my elder daughter Merab, her will I give thee for a wife: only be thou valiant for me, and fight the LORD’S battles. For Saul said, Let not my hand be upon him, but let the hand of the Philistines be upon him.1 18And David said to Saul, Who am I? and what is my life, or my father’s family in Israel, that I should be son in law to the king? 19But it came to pass at the time when Merab Saul’s daughter should have been given to David, that she was given to Adriel the Meholathite for a wife. 20And Michal Saul’s daughter loved David: and they told Saul, and the thing pleased him.2 21And Saul said, I will give her to him, that she may be a snare to him, and that the hand of the Philistines may be against him. Therefore Saul said to David, Thou shalt this day be my son in law in the one of the two.