Ira the Jairite - Not mentioned before: perhaps the same as “Ira an Ithrite” (marginal reference), i. e., an inhabitant of Jattir in the hill country of Judah Joshua 15:48; 1 Samuel 30:27. Perhaps we ought to read “Ithrite,” for “Jairite.”
A chief ruler ... about David - More simply and clearly, “was David’s kohen” (2 Samuel 8:18 note). In the early part oph David’s reign his own ons were כהן kôhên (chief rulers). The deaths of Amnon and Absalom, and the dissensions in the family, had probably caused the change of policy in this respect.