John Gill Bible Commentary

Then Abner called to Joab,.... For having now a troop of men with him, he could stop with the greater safety; and being on an hill, and perhaps Joab on one opposite to him, could call to him, so as to be heard: and said, shall the sword devour for ever? slay men, and devour their blood. See Jer 46:10. That he was not thoughtful of, nor concerned about, when he set the young men to fighting before the battle, and called it play to wound and shed the blood of each other; but now the battle going against him, he complains of the devouring sword; and though it had been employed but a few hours, it seemed long to him, a sort of an eternity: knowest thou not that it will be bitterness in the latter end? since it might issue in the death of himself, or of Joab, or of both, as it had in Asahel, or, however, in the death of a multitude of others; and which at last would cause bitter reflection in the prosecutors of the war: how long shall it be then ere thou bid the people return from following their brethren? he pleads relation, that the men of Israel and the men of Judah were brethren; so they were by nation and religion, and therefore should not pursue one another to destruction; but who was the aggressor? It was Abner, that brought his forces against Judah; the men of David acted only on the defensive.