21 Then Joab said to the Cushite, Go and give the king word of what you have seen. And the Cushite, making a sign of respect to Joab, went off running. 22 Then Ahimaaz, the son of Zadok, said to Joab again, Whatever may come of it, let me go after the Cushite. And Joab said, Why have you a desire to go, my son, seeing that you will get no reward for your news? 23 Whatever may come of it, he said, I will go. Then he said to him, Go. So Ahimaaz went running by the lowland road and overtook the Cushite. 24 Now David was seated between the two town doors; and the watchman went up to the roof of the doorways, on the wall, and, lifting up his eyes, saw a man running by himself. 25 And the watchman gave news of it to the king. And the king said, If he is coming by himself, then he has news. And the man was travelling quickly, and came near.

Matthew Henry's Commentary on 2 Samuel 18:21-25

Commentary on 2 Samuel 18:19-33

(Read 2 Samuel 18:19-33)

By directing David to give God thanks for his victory, Ahimaaz prepared him for the news of his son's death. The more our hearts are fixed and enlarged, in thanksgiving to God for our mercies, the better disposed we shall be to bear with patience the afflictions mixed with them. Some think David's wish arose from concern about Absalom's everlasting state; but he rather seems to have spoken without due thought. He is to be blamed for showing so great fondness for a graceless son. Also for quarrelling with Divine justice. And for opposing the justice of the nation, which, as king, he had to administer, and which ought to be preferred before natural affection. The best men are not always in a good frame; we are apt to over-grieve for what we over-loved. But while we learn from this example to watch and pray against sinful indulgence, or neglect of our children, may we not, in David, perceive a shadow of the Saviour's love, who wept over, prayed for, and even suffered death for mankind, though vile rebels and enemies.