2 Samuel 19:5

And Joab … said. Joab's speech puts the alternative in a very incisive and even rude way before the king. But what he says is true, namely, that Absalom's success would inevitably have been followed by the massacre, not only of David himself, but of his sons and daughters, and of the women who had accompanied him in his flight. Nor would it have stopped there. but the officers of his court, the captains of his army, his mighties, and all who had long eared for and loved him would have been put to the sword. It was this horrible certainty, according to Oriental usage, which made Absalom's rebellion so abominable, and which steeled the heart of Joab against him when he saw him hanging in the tree. He regarded him as a fratricide and parricide, who had plotted murder on a large scale; and Joab was not made milder by the thought that this would have included himself and the heroes who had made David's throne so great. With stern good sense he, therefore, bids the king suppress his mere personal feelings, and leave the chamber in which he had concealed himself, to go forth and "speak to the heart of his servants," that is, thank and praise them in a friendly manner. For otherwise they would disperse and leave him; and this would be followed by the uprise of some other claimant of the throne—some relative, perhaps, of Saul, backed by the tribes of Benjamin and Ephraim; and David, abandoned by the nation, would fall an easy victim, with all his family, of this second rebellion. Absalom's rapid success proved that David had many enemies, and without great prudence he might be left at Mahanaim as powerless as Ishbeshoth had been. The long delay between the death of this puppet king and David's appointment to be sovereign of all Israel was probably owing to the same want of enthusiasm for David which had made the nation transfer its allegiance so lightly to the handsome Absalom. But with all his good sense Joab was coarse and rude. He was, moreover, utterly incapable of understanding David's real feelings. He saw only a father giving way to an exaggerated loss for a handsome but worthless son. David really was condemning himself for having brought lust and murder into his own house by abominable sin.