Knowing that he that is such is subverted - Literally, “is turned out;” or, “is changed,” i. e., for the worse. He has gone from the right way, and therefore he should be rejected.
And sinneth, being condemned of himself - His own conscience condemns him. He will approve the sentence, for he knows that he is wrong; and his self-condemnation will be punishment sufficient. His own course, in attempting a division or schism in the church, shows him that it is right that he should be separated from the communion of Christians. He that attempts to rend the church, without a good reason, should himself be separated from it.