Matthew Henry's Complete Bible Commentary
Verses 15—19
Here is, 1. A new attempt of the Syrians to recover their lost honour and to check the progress of David’s victorious arms. The forces that were lately dispersed rallied again, and gathered themselves together, 2 Samuel 10:15. Even the baffled cause will make head as long as there is any life in it; the enemies of the Son of David do so, Matthew 22:34, 19:19. These, being conscious of their insufficiency, called in the aid of their allies and dependencies on the other side of the river (2 Samuel 10:16), and, being thus recruited, they hoped to make their part good against Israel, but they knew not the thoughts of the Lord, for he gathered them as sheaves into the floor; see Micah 4:11-4:13. 2. The defeat of this attempt by the vigilance and valour of David, who, upon notice of their design, resolved not to stay till they attacked him, but went in person at the head of his army over Jordan (2 Samuel 10:17), and, in a pitched battle, routed the Syrians (2 Samuel 10:18), slew 7000 men, who belonged to 700 chariots, and 40,000 other soldiers, horse and foot, as appears by comparing 1 Chronicles 19:18. Their general was killed in the battle, and David came home in triumph, no doubt. 3. The consequence of this victory over the Syrians. (1.) David gained several tributaries, 2 Samuel 10:19. The kings, or petty princes, that had been subject to Hadarezer, when they saw how powerful David was, very wisely made peace with Israel, whom they found they could not make war with, and served them, since they were able to give them protection. Thus the promise made to Abraham (Genesis 15:18), and repeated to Joshua (2 Samuel 1:4), that the borders of Israel should extend to the river Euphrates, was performed, at length. (2.) The Ammonites lost their old allies: The Syrians feared to help the children of Ammon, not because they had an unrighteous cause (justifying a crime which was a breach of the law of nations), but because they found it was an unsuccessful cause. It is dangerous helping those that have God against them; for, when they fall, their helpers will fall with them. MHBCC 278.11
Jesus Christ, the Son of David, sent his ambassadors, his apostles and ministers, after all his servants the prophets, to the Jewish church and nation; but they treated them shamefully, as Hanun did David’s ambassadors, mocked them, abused them, slew them; and it was this that filled the measure of their iniquity, and brought upon them ruin without remedy (Matthew 21:35, 21:41, 22:7, 26:16); for Christ takes the affronts and injuries done to his ministers as done to himself and will avenge them accordingly. MHBCC 278.12