The Septuagint adds, what is a good explanation, "but he did not vex the spirit of Amnon his son, because he loved him, because he was his first-born." This want of justice in David's conduct, and favoritism to Amnon, probably rankled in Absalom's heart, and was the first seed of his after rebellion.

But when King David heard - To this verse the Septuagint add the following words: Και ουκ ελυπησε το πνευμα Αμνων του υἱου αυτου, ὁτι ηγαπα αυτον, ὁτι πρωτοτοκος αυτου ην; "But he would not grieve the soul of Amnon his son, for he loved him, because he was his first-born." The same addition is found in the Vulgate and in Josephus, and it is possible that this once made a part of the Hebrew text.

But when King David heard of all these things,.... Of Amnon's ravishing Tamar, and turning her out of doors in that inhuman manner he did, and of her distress upon it:

he was very wroth; with Amnon; but we read not of any reproof he gave him, nor of any punishment inflicted on him by him. Abarbinel thinks the reason why he was not punished was because his sin was not cognizable by a court of judicature, nor was punishable by any way, or with any kind of death inflicted by the sanhedrim, as stoning, burning, &c. nor even by scourging, because there were no witnesses; but the punishment of it was cutting off, i.e. by the hand of God. The Jews say (e) a law was made on this, that virgins or unmarried persons should not be alone; for if this was done to the daughter of a king, much more might it be done to the daughter of a private man; and if to a modest person, much more to an impudent one.

(e) T. Bab. Sanhedrin, fol. 21. 1.

When David heard "all these things," he became very wrathful; but Absalom did not speak to Amnon "from good to evil" (i.e., either good or evil, not a single word: Genesis 24:50), because he hated him for having humbled his sister. The lxx add to the words "he (David) was very wroth," the following clause: "He did not trouble the spirit of Amnon his son, because he loved him, for he was his first-born." This probably gives the true reason why David let such a crime as Amnon's go unpunished, when the law enjoined that incest should be punished with death (Leviticus 20:17); at the same time it is nothing but a subjective conjecture of the translators, and does not warrant us in altering the text. The fact that David was contented to be simply angry is probably to be accounted for partly from his own consciousness of guilt, since he himself had been guilty of adultery; but it arose chiefly from his indulgent affection towards his sons, and his consequent want of discipline. This weakness in his character bore very bitter fruit.

But when king David heard of all these things, he was very wroth.

13:21 Wroth - With Amnon: whom yet he did not punish, at least so severely as he should either from the consciousness of his own guilt in the like kind; or, from that foolish indulgence which he often shewed to his children.

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.