There were seven churches listed. Each one had a fault and a good part to them. There were probably even more house churches in individual homes or towns. The churches listed in Revelation 1 are: The church at Ephesus, Smyrna, Thyatira, Sardis, Philadelphia, Pergamum and Laodicea.
Jesus was a Jew. A descendant of Jewish King David. He had a Jewish mother who had Jewish parents. He conformed to the requirements of Mosaic Law from the time of His circumcision until the Pasch, the night before His crucifixion. The existing Church of God during Christ's days on earth was the Jewish Church.