(17) He gathered . . . and passed.--David, hearing of the great Syrian rally, now took the field in person. Joab may have been with him, but more probably was employed at the south in holding the Ammonites in check and preventing their forming a junction with their confederates.

Verse 17. - David... gathered all Israel together. Some commentators see in this an indication of dissatisfaction with Joab. Really it was a matter of course that in so great a war the king should place himself at the head of his levies. For not only was he possessed of great military genius, but his personal presence would make the men of Israel, a race of sturdy free men, assemble in greater numbers, and would give them confidence. If David himself went there would be no shirking the war and finding excuses to stay at home, and in the camp there would be prompt alacrity and zeal.

10:15-19 Here is a new attempt of the Syrians. 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. But now the promise made to Abraham, Ge 15:18, and repeated to Joshua, Jos 1:4, that the borders of Israel should extend to the river Euphrates, was performed. Learn hence, that it is dangerous to help those who have God against them; for when they fall, their helpers will fall with them.And when it was told David,.... What preparations the Syrians were making to fight him, and where they were:

he gathered all Israel together; all the fighting men in the country:

and passed over Jordan, and came to Helam: which, according to Bunting (b), was twenty miles from Jerusalem. David seems to have gone himself in person to this war:

and the Syrians set themselves in array against David, and fought with him; they formed themselves in a line of battle, and attacked him first, being eager to fight, and perhaps confident of victory, because of their numbers.

(b) Travels, &c. p. 140, 141.