1 Samuel 18:22-25

22And Saul commanded his servants, Speak with David secretly, saying, Behold, the king has delight in thee, and all his servants love thee: now therefore be the king's son-in-law.

23And Saul's servants spoke those words in the ears of David. And David said, Is it a light thing in your eyes to be the king's son-in-law, seeing that I am a poor man, and lightly esteemed?

24And the servants of Saul told him, saying, On this manner did David speak.

25And Saul said, Thus shall ye say to David: The king does not desire any dowry, but a hundred foreskins of the Philistines, to be avenged of the king's enemies. But Saul thought to make David fall by the hand of the Philistines.