So Saul’s servants spoke these words privately to David. David replied, “Is becoming the king’s son-in-law something insignificant to you? I’m just a poor and lightly-esteemed man!”

So his servants told David these things and David agreed to become the king’s son-in-law. Now the specified time had not yet expired

Then Saul instructed his servants, “Tell David secretly, ‘The king is pleased with you, and all his servants like you. So now become the king’s son-in-law.”

when David, along with his men, went out and struck down two hundred Philistine men. David brought their foreskins and presented all of them to the king so he could become the king’s son-in-law. Saul then gave him his daughter Michal in marriage.