23 And it came to pass after two full years, that Absalom had sheep-shearers in Baal-hazor, which is beside Ephraim: and Absalom invited all the king's sons. 24 And Absalom came to the king, and said, Behold now, thy servant hath sheep-shearers; let the king, I pray thee, and his servants go with thy servant. 25 And the king said to Absalom, Nay, my son, let us not all go, lest we be burdensome unto thee. And he pressed him: howbeit he would not go, but blessed him. 26 Then said Absalom, If not, I pray thee, let my brother Amnon go with us. And the king said unto him, Why should he go with thee? 27 But Absalom pressed him, and he let Amnon and all the king's sons go with him. 28 And Absalom commanded his servants, saying, Mark ye now, when Amnon's heart is merry with wine; and when I say unto you, Smite Amnon, then kill him; fear not; have not I commanded you? be courageous, and be valiant. 29 And the servants of Absalom did unto Amnon as Absalom had commanded. Then all the king's sons arose, and every man gat him up upon his mule, and fled.
30 And it came to pass, while they were in the way, that the tidings came to David, saying, Absalom hath slain all the king's sons, and there is not one of them left. 31 Then the king arose, and rent his garments, and lay on the earth; and all his servants stood by with their clothes rent. 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. 34 But Absalom fled. And the young man that kept the watch lifted up his eyes, and looked, and, behold, there came much people by the way of the hill-side behind him. 35 And Jonadab said unto the king, Behold, the king's sons are come: as thy servant said, so it is. 36 And it came to pass, as soon as he had made an end of speaking, that, behold, the king's sons came, and lifted up their voice, and wept: and the king also and all his servants wept very sore. 37 But Absalom fled, and went to Talmai the son of Ammihur, king of Geshur. And [David] mourned for his son every day. 38 So Absalom fled, and went to Geshur, and was there three years.
Matthew Henry's Commentary on 2 Samuel 13:23-38
Commentary on 2 Samuel 13:21-29
(Read 2 Samuel 13:21-29)
Observe the aggravations of Absalom's sin: he would have Ammon slain, when least fit to go out of the world. He engaged his servants in the guilt. Those servants are ill-taught who obey wicked masters, against God's commands. Indulged children always prove crosses to godly parents, whose foolish love leads them to neglect their duty to God.
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.