Adam Clarke on Acts 24:11

There are yet but twelve days - This is his reply to their charge of sedition; the improbability of which is shown from the short time he had spent in Jerusalem, quite insufficient to organize a sedition of any kind; nor could a single proof be furnished that he had attempted to seduce any man, or unhinge any person from his allegiance by subtle disputations, either in the temple, the synagogues, or the city. So that this charge necessarily fell to the ground, self-confuted, unless they could bring substantial proof against him, which he challenges them to do.