And he conferred with Joab - Joab well knew, if he made the new king, he would necessarily be continued in the command of the army, and so govern him.
Joab‘s defection on this occasion, after his faithful adherence to David during the troubles caused by Absalom 1 Chronicles 22:9 and by his preference for the character of Adonijah. He may also have thought that Adonijah, as the eldest son 1 Kings 1:5, had almost a right to succeed.
Abiathar‘s defection is still more surprising than Joab‘s. For his history, see 1 Samuel 22:20 note. Hereto, David and he had been the firmest of friends. It has been conjectured that he had grown jealous of Zadok, and feared being supplanted by him.