Behold, [they have] there with them two sons, Ahimaaz, Zadok's
[son], and Jonathan, Abiathar's [son]
As in ( 2 Samuel 15:27 ) ; not that they were in the city with them, but they were near it, ( 2 Samuel 17:17 ) ; with whom they had a communication:
and by whom ye shall send unto me everything that ye can hear;
that is, by the sons of the priests; he telling the priests how things were at court, and they sending their sons with messages to David; which was a good scheme to get intelligence, and easy to be put into execution.