The king also said to Zadok the priest, “Are you not a seer? Return to the city in peace—you with your son Ahimaaz, and Abiathar with his son Jonathan.
Here we have, I. The fidelity of the priests and Levites and their firm adherence to David and his interest. They knew David's great affection to them and their office, notwithstanding his failings. The method Absalom took to gain people's affections made no impression upon them; he had little religion in him, and therefore they steadily adhered to David.
Commenting on 2 Samuel 15:24-30
And the king said unto Zadok the priest, art not thou a seer?.... A prophet, as well as a priest; see Sa1 9:9; or a seeing, knowing, man; one that can penetrate into men and things, and so might be of more service to David at Jerusalem than with him: wherefore he said to him: return into the city in peace; to the city of...
Art not thou a seer? return into the city in peace - That is, As thou art the only organ of the public worship, that worship cannot be carried on without thee; and as thou art the priest of God, thou hast no cause to fear for thy personal safety: the nation has not abandoned their God, though they have abandoned their king.