30 Now while they were on their way, news was given to David that Absalom had put to death all the sons of the king and that not one of them was still living.

Matthew Henry's Commentary on 2 Samuel 13:30

Commentary on 2 Samuel 13:30-39

(Read 2 Samuel 13:30-39)

Jonadab was as guilty of Ammon's death, as of his sin; such false friends do they prove, who counsel us to do wickedly. Instead of loathing Absalom as a murderer, David, after a time, longed to go forth to him. This was David's infirmity: God saw something in his heart that made a difference, else we should have thought that he, as much as Eli, honoured his sons more than God.