(1) We have good ground for believing that, besides these seven churches of Asia, there were other churches in existence in the same district at the time when the Apostle wrote. One of the early fathers speaks of churches at Magnesia and Tralles. It is also possible that there were churches at Coloss?and Hierapolis, although these cities had suffered from an earthquake shortly after the days of St. Paul. Yet St. John addressed himself not to seven, but to "the seven churches which are in Asia," as if there were no more churches in the province.[31] More, however, there certainly were; and he cannot therefore have intended to address them all. He makes a selection, without saying that he does so; and it is a natural supposition that his selection is designed to represent the universal Church. (2) Importance must be attached to the number seven. Every reader of the book of Revelation is familiar with the singular part played by that number in its structure, and with the fact that (unless chap. xvii. 9 be an exception) it never means that numeral alone. It is the number of unity in diversity, of unity in that manifoldness of operation which alone entitles it to the name of unity. Such expressions, therefore, as the "seven Spirits of God" or the "seven eyes of the Lamb," are evidently symbolical. The same idea must be carried through all the notices of the number, unless there be something in the context clearly leading to a different conclusion. Nothing of that kind exists here. Were these two chapters indeed out of harmony with the rest of the book, or had they little or no relation to it, it might be urged that they were simply historical, and that no deeper meaning was to be sought in them than that lying on the surface. We have already seen, however, that their connexion with the other chapters is of the closest kind; and we cannot therefore avoid bringing them under the scope of the same principles of interpretation as are elsewhere applicable. Their number--seven--must thus be regarded as typical of unity, and the seven churches as representative of the one universal Church. (3) The nature of the call to the hearers of each epistle to give heed to the words addressed to them leads to the same conclusion. Had each epistle been designed only for those to whom it was immediately sent, that call would probably have been addressed to them alone. Instead of this it is couched in the most general form: _He that hath an ear, let him hear what the Spirit saith to the churches._