2 Samuel 24:3

Why doth my lord the king delight in this thing? Joab was an unscrupulous and irreligious man; but he was clear headed, and far more statesmanlike than David ( 2 Samuel 19:5-7 ). He saw whither the king was drifting, and that the increase of the royal power, resulting from successful war, would be fatal to the liberties of Israel. Probably, too, though he had consented to carry out Uriah's murder, yet he despised David for it. When he had murdered Abner to avenge Asahel, David had deprived him of his command, and he had to endure a long period of disgrace; and now David uses him to murder one altogether innocent. Joab, we may feel sure, noted the degradation of David's character, and drew the conclusion that he was not the man to be trusted at the head of a military despotism. Warned thus by what he saw, his mind reverted to the principles of the theocracy, and their truth and value became more clear to his understanding; and honourably he remonstrates with David for violating them.