2 Samuel 9:2
9:2 Now there was a servant from Saul’s house named Ziba, so he was summoned to David. The king asked him, “Are you Ziba?” He replied, “At your service.”
2 Samuel 9:6
9:6 When Mephibosheth son of Jonathan, the son of Saul, came to David, he bowed low with his face toward the ground. David said, “Mephibosheth?” He replied, “Yes, at your service.”