Although he was afraid, he did not wish to show his weak side by immediately freeing the Jewish prisoner from his bonds.
He commanded the chief priests and the whole Sanhedrin to assemble (see the note on Acts 4:5 and following). This command clearly shows how the Roman government had lowered the authority of the Jerusalem Sanhedrin by this time, even in matters belonging to the sphere of religion. Only a shadow of independence remained.
Not only the procurator, the governor of the province, but even an ordinary regimental commander orders the Jerusalem Sanhedrin to assemble. Once it had been a mighty force, considering itself able to direct not only religious, but also public affairs of Jews throughout the world, wherever they were.
And indeed, the former spirit was no longer in this Sanhedrin.
To assemble: the expression indicates the usual official meeting of the Sanhedrin, not at the Roman tribune’s quarters, but in the customary place of its official sessions. This was probably, according to Acts 23:10, in one of the temple buildings (see the note on Jn 7:32).
Having brought Paul out of the Antonia fortress, he set him before them in the council chamber. As is clear from what follows, he himself remained there, probably foreseeing a storm (compare Acts 23:10).