2 Samuel 9:3
And the king said, Is there not yet any of the house of Saul, that I may shew the kindness of God unto him? And Ziba said unto the king, Jonathan hath yet a son, which is lame on his feet. And the king said, Is there not yet any of the house of Saul, that I may shew the kindness of God unto him? And Ziba said unto the king, Jonathan hath yet a son, which is lame on his feet.
The inquiry recorded here is David's, asking if any member of Saul's house still remained to whom he might extend the kindness of God. That kindness was sought specifically for Jonathan's sake. In answer Ziba informed the king that Jonathan still had a surviving son, Mephibosheth. That son was lame in both feet, a condition dating from his childhood.
He had become crippled when his nurse dropped him while fleeing in haste after Saul's defeat by the Philistines. In fulfillment of his covenant with Jonathan, David restored to him Saul's private possessions. He also received him as a regular guest at the royal table. By such generous and courteous treatment David overcame Mephibosheth's prejudice against him, winning him to devoted loyalty.