2 Samuel 13:30
And it came to pass, while they were in the way, that tidings came to David, saying, Absalom hath slain all the king’s sons, and there is not one of them left. And it came to pass, while they were in the way, that tidings came to David, saying, Absalom hath slain all the king’s sons, and there is not one of them left.
While the king's sons were on the way back from Absalom's feast, tidings reached David that Absalom had slain all the king's sons and that not one of them was left. The report was false, yet it was believed and brought terrible grief to the court. David arose and tore his garments and lay on the earth, and all his servants stood by with their clothes rent. There was very sore weeping by the king and by his servants over what they supposed had happened.
The return of the sons themselves proved the report false, for Amnon alone had been slain. He had fallen by Absalom's command, in revenge that Absalom had concealed for two full years. That revenge answered Amnon's doubly guilty crime, which had gone unpunished. The killing behind the false tidings was judgment already meted out to David for his own sin. It formed part of the four deaths of his sons required by his own fourfold sentence, so that twofold judgment had now fallen as the result of his sin and of his self-condemned failure to punish Amnon.