2 Samuel 15:37

So Hushai David's friend came into the city
The city of Jerusalem, by the direction and persuasion of David, and in obedience to him, in order to serve him to the uttermost:

and Absalom came into Jerusalem:
just at the same time; so that he knew not that Hushai had been out of it, and been with David, and which also appears from what he said to him, ( 2 Samuel 16:17 ) .