1 Samuel 18:25-27

25Then Saul said, “Thus you shall say to David: ‘The king does not desire any dowry but one hundred foreskins of the Philistines, to take vengeance on the king’s enemies.’ ” But Saul thought to make David fall by the hand of the Philistines.

26So when his servants told David these words, it pleased David well to become the king’s son-in-law. Now the days had not expired;

27therefore David arose and went, he and his men, and killed two hundred men of the Philistines. And David brought their foreskins, and they gave them in full count to the king, that he might become the king’s son-in-law. Then Saul gave him Michal his daughter as a wife.