New Defender's Study Bible Notes
2:9 say they are Jews. These must have been Gentile converts of the Judaizers, who were trying to impose Judaism, with its law and priesthood, on Christianity. Just as men claiming to be apostles, who were not, were disturbing the church at Ephesus, so at Smyrna men claiming to have become Jews, who were not, were plaguing the church there. These two groups of heretics were beginning a corruption of Christianity which would eventually pervade the church for a thousand years, imposing an imagined apostolic succession and continuing priesthood, both of which would subjugate the ordinary people in the churches in a “Nicolaitan” hierarchy. As the false apostles were ministers of Satan (II Corinthians 11:13-15), so these false Jews had become—unknowingly perhaps—a synagogue of Satan.