32 And Jonadab, the son of Shimeah, David's brother, answered and said, Let not my lord suppose that they have killed all the young men the king's sons; for Amnon only is dead; for by the appointment of Absalom this hath been determined from the day that he forced his sister Tamar. 33 Now therefore let not my lord the king take the thing to his heart, to think that all the king's sons are dead; for Amnon only is dead.
Matthew Henry's Commentary on 2 Samuel 13:32-33
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.