31 As they were trying to kill him, word came to the captain of the guard, "A riot! The whole city's boiling over!" 32 He acted swiftly. His soldiers and centurions ran to the scene at once. As soon as the mob saw the captain and his soldiers, they quit beating Paul. 33 The captain came up and put Paul under arrest. He first ordered him handcuffed, and then asked who he was and what he had done. 34 All he got from the crowd were shouts, one yelling this, another that. It was impossible to tell one word from another in the mob hysteria, so the captain ordered Paul taken to the military barracks. 35 But when they got to the Temple steps, the mob became so violent that the soldiers had to carry Paul. 36 As they carried him away, the crowd followed, shouting, "Kill him! Kill him!"
37 When they got to the barracks and were about to go in, Paul said to the captain, "Can I say something to you?" 38 I thought you were the Egyptian who not long ago started a riot here, and then hid out in the desert with his four thousand thugs."
Matthew Henry's Commentary on Acts 21:31-38
Commentary on Acts 21:27-40
(Read Acts 21:27-40)
In the temple, where Paul should have been protected as in a place of safety, he was violently set upon. They falsely charged him with ill doctrine and ill practice against the Mosaic ceremonies. It is no new thing for those who mean honestly and act regularly, to have things laid to their charge which they know not and never thought of. It is common for the wise and good to have that charged against them by malicious people, with which they thought to have obliged them. God often makes those a protection to his people, who have no affection to them, but only have compassion for sufferers, and regard to the public peace. And here see what false, mistaken notions of good people and good ministers, many run away with. But God seasonably interposes for the safety of his servants, from wicked and unreasonable men; and gives them opportunities to speak for themselves, to plead for the Redeemer, and to spread abroad his glorious gospel.