2 Samuel 9:6-8

He fell on his face and did reverence As the manner was when men came into the presence of the king or king's son; for thus David himself prostrated himself before Jonathan, 1 Samuel 20:41. I will restore thee all the land of Saul thy father That is, according to our mode of speaking, thy grand-father. This land was, perhaps, the family estate of Saul, to which he had annexed other lands for his private use. But because they had been taken by virtue of Saul's royal prerogative, therefore they were now considered, and perhaps had been seized, as appertaining to his successor on the throne, David. And he bowed himself It is good to have the heart humbled under humbling providences. If, when divine providence brings our condition down, divine grace bring our spirits down, we shall be easy. That thou shouldest look on such a dead dog This is a high expression of humility; for a dog was accounted a vile and unclean creature, and a dead dog as of no use at all. And it is likely that Mephibosheth spoke this, both in regard of his bodily infirmity of lameness, and because he was not instructed in, or had no natural genius for affairs of state.