Adam Clarke on 2 Kings 11:4

And the seventh year Jehoiada sent - He had certainly sounded them all, and brought them into the interests of the young king, before this time; the plot having been laid, and now ripe for execution, he brings the chief officers of the army and those of the body guard into the temple, and there binds them by an oath of secrecy, and shows them the king's son, in whose behalf they are to rise.