Albert Barnes Commentary Acts 21:35

"And when he came upon the stairs, so it was that he was borne of the soldiers for the violence of the crowd;" — Acts 21:35 (ASV)

Upon the stairs. The stairs which led from the temple to the tower of Antonia. Josephus says, (Jewish Wars, Book 5, Chapter 5, § 8), that the tower of Antonia "was situated at the corner of two cloisters of the court of the temple—of that on the west, and of that on the north; it was erected on a rock of fifty cubits [seventy-five feet] in height, and was on a great precipice. On the corner where it joined to the two cloisters of the temple, it had passages down to them both, through which the guards went several ways among the cloisters with their arms on the Jewish festivals," etc.

It was on these stairs, as the soldiers were returning, that the tumult was so great, or the crowd so dense, that they were obliged to bear him along to rescue him from their violence.

Violence of the people. The rush of the multitude.