18:1 David took command as he had in former days. In recent years, his life had been characterized by indecisiveness and moral paralysis. At this time he began to take charge and do his duty.
18:12-14 This man had caught Joab in his hypocrisy. He knew Joab would have turned on him for killing the man if the king had found out about it. Joab could not answer, but only dismissed him. Those about to do evil often do not take the time to consider what they are about to do. They don’t care whether or not it is right or lawful. Don’t rush into action without thinking. Consider whether what you are about to do is right or wrong.
18:29 Although he reached the city first, Ahimaaz was afraid to tell the king the truth about the death of his son Absalom.
18:33 Why was David so upset over the death of his rebel son? (1) David realized that he, in part, was responsible for Absalom’s death. Nathan the prophet had said that because David had killed Uriah, his own sons would rebel against him. (2) David was angry at Joab and his officers for killing Absalom against his wishes. (3) David truly loved his son, even though Absalom did nothing to deserve his love. It would have been kinder and more loving to deal with Absalom and his runaway ego when he was younger.