15:16 After him - Or, on foot, which the king chose to do, to humble himself under the hand of God; to encourage his companions in this hard and comfortless march; and to move compassion in his people towards him. Concubines - For he supposed that their sex would protect them, and their relation to David would gain them some respect, or at least, safety from his son.
15:13-23 David determined to quit Jerusalem. He took this resolve, as a penitent submitting to the rod. Before unrighteous Absalom he could justify himself, and stand out; but before the righteous God he must condemn himself, and yield to his judgments. Thus he accepts the punishment of his sin. And good men, when they themselves suffer, are anxious that others should not be led to suffer with them. He compelled none; those whose hearts were with Absalom, to Absalom let them go, and so shall their doom be. Thus Christ enlists none but willing followers. David cannot bear to think that Ittai, a stranger and an exile, a proselyte and a new convert, who ought to be encouraged and made easy, should meet with hard usage. But such value has Ittai for David's wisdom and goodness, that he will not leave him. He is a friend indeed, who loves at all times, and will adhere to us in adversity. Let us cleave to the Son of David, with full purpose of heart, and neither life nor death shall separate us from his love.