Charles Ellicott Commentary Acts 21:31

"And as they were seeking to kill him, tidings came up to the chief captain of the band, that all Jerusalem was in confusion." — Acts 21:31 (ASV)

The chief captain of the band.—On the word “band,” and its relation to the Latin “cohort,” see Notes on Acts 10:1; Matthew 27:27. On the word for “chief captain” (literally, chiliarch, or “captain of a thousand men,” the cohort being the sixth part of the legion, which consisted of 6,000), see Note on Matthew 8:29.

They were stationed in the tower known as Antonia. This tower was built by Herod the Great and named in honour of the Triumvir. It stood on the north-west side of the Temple area, on a rock, with a turret at each corner, and two flights of stairs leading to the arcades on the northern and western sides of the Temple.

The Roman garrison was obviously stationed there to command the crowds of pilgrims and was likely to be on the alert at a time like the Pentecost Feast. The Procurator Felix, however, was at the time at Caesarea.

The next verse shows that their appearance was sufficient to strike some kind of awe into the turbulent mob at once. Once again the Apostle owed his safety from violence to the interposition of the civil power (See Notes on Acts 18:14-17).

The “beating” would seem to have been rough treatment with the fists rather than any regular punishment.