John Lightfoot on John 9:22

[He should be put out of the synagogue.] So chapter 16:2: Granting that this is spoken of excommunication, the question may be, Whether it is to be understood of the ordinary excommunication, that is, from this or that synagogue; or the extraordinary, that is, a cutting off from the whole congregation of Israel.

"Whoever is excommunicated by the president of the Sanhedrim is cut off from the whole congregation of Israel": and if so, then much more if it be by the vote of the whole Sanhedrim. And it seems by that speech, they cast him out, verse 34, that word out, was added for such a signification.

But suppose we, it might be understood of the ordinary excommunication; among all the four-and-twenty reasons of excommunication, which should it be for which this was decreed, viz. that "if any man did confess that Jesus was the Christ, he should be put out of the synagogue?" The elders of the Sanhedrim, perhaps, would answer, what upon other occasions is frequently said and done by them, "It is decreed for the necessity of the time."