1 Samuel 18:25

“If her father absolutely refuses to give her to him, he shall pay money equal to the dowry for virgins.

Then Saul said to David, “Here is my older daughter Merab; I will give her to you as a wife; only be a man of valor for me and fight Yahweh’s battles.” For Saul thought, “My hand shall not be against him, but let the hand of the Philistines be against him.”

So David sent messengers to Ish-bosheth, Saul’s son, saying, “Give me my wife Michal, to whom I was betrothed for one hundred foreskins of the Philistines.”