1909 Catholic Dictionary
They are Ephesus, Smyrna, Pergamus, Thyatira, Sardis, Philadelphia, and Laodicea, mentioned in Apocalypse, 1-3, where Saint John, on the island of Patmos, was commanded to send to their bishops instructions and admonitions, in which the Church is praised or blamed with reference to past trials and told of a greater one to come in connection with the coming of Christ.