John Gills Exposition of the Bible Commentary - 2 Samuel 18:2
And David sent forth a third part of the people under the hand of Joab ,.... Very likely that which made the centre of the army, since Joab was the general of the army; though this distribution was made when David thought to have headed the army himself, and so made with respect to that: and a third part under the hand of Abishai the son of Zeruiah, Joab's brother ; who was next to Joab in the army, and fought with him against the Syrians and Ammonites, 2 Samuel 10:10 , and a third... read more
Matthew Henry's Complete Commentary - 2 Samuel 18:1-8
Which way David raised an army here, and what reinforcements were sent him, we are not told; many, it is likely, from all the coasts of Israel, at least from the neighbouring tribes, came in to his assistance, so that, by degrees, he was able to make head against Absalom, as Ahithophel foresaw. Now here we have, I. His army numbered and marshalled, 2 Sam. 18:1, 2. He had, no doubt, committed his cause to God by prayer, for that was his relief in all his afflictions; and then he took an account... read more