Revelation 1:4 note 2
42 Asia was a province of the ancient Roman Empire, and in that province were the seven cities mentioned in v. 11. The seven churches were in those seven cities, respectively; they were not all in one city. This book does not deal with the one universal church but with the local churches in many cities. First, in Matt. 16:18 the church is revealed as universal, and then in Matt. 18:17 it is revealed as local. In Acts the church was practiced in the way of local churches, such as the church in Jerusalem (Acts 8:1), the church in Antioch (Acts 13:1), the church in Ephesus (Acts 20:17), and the churches in the provinces of Syria and Cilicia (Acts 15:41). The Epistles were written to the local churches, except for a few written to individuals. Not one was written to the universal church. Without the local churches, the universal church has no practicality or actuality. The universal church is realized in the local churches. Knowing the church in its universal aspect must be consummated in knowing the church in its local aspect. It is a great advance for us to know and practice the local churches. Concerning the church, the book of Revelation is in the advanced stage. To know this book, we must advance from the understanding of the universal church to the realization and practice of the local churches, because this book is written to the local churches. Only those who are in the local churches are positioned rightly, with the right angle and the proper perspective, to see the visions in this book.
The Triune God is expressed in Christ (John 1:1, 14; 1 Tim. 3:16; Col. 2:9); Christ is realized and experienced as the Spirit (John 14:16-18; 1 Cor. 15:45; 2 Cor. 3:17; Rom. 8:9; Phil. 1:19) and is expressed in His Body, the universal church (Eph. 1:22-23; 1 Cor. 12:12; Eph. 4:4); and the universal church is expressed in the local churches. Therefore, to know and experience God, we need to know and experience Christ; to know and experience Christ, we need to participate in the universal church through the Spirit; and to participate in the universal church, we need to participate in the local churches.