20 The mystery of the seven stars which thou sawest in my right hand, and the seven golden candlesticks. The seven stars are the angels of the seven churches: and the seven candlesticks which thou sawest are the seven churches.
But the path of those belonging to the church surrounds the whole world. It possesses the sure tradition from the apostles and allows us to see that the faith of all is one and the same, since all receive one and the same God the Father. All believe in the same dispensation regarding the incarnation of the Son of God. All are cognizant of the same gift of the Spirit. All are conversant with the same commandments. All preserve the same form of ecclesiastical constitution. And all expect the same advent of the Lord and await the same salvation of the complete man, that is, of the soul and body. Undoubtedly the preaching of the church is true and steadfast, in which one and the same way of salvation is shown throughout the whole world. For to her is entrusted the light of God. Therefore the “wisdom” of God, by means of which she saves all people, “is declared in [its] going forth; it speaks faithfully in the streets, is preached on the tops of the walls, and speaks continually in the gates of the city.” For the church preaches the truth everywhere, and she is the seven-branched candlestick that bears the light of Christ.
Therefore he has trifled both with his own "spirit," and with "the angel of the Church," and with "the power of the Lord," if he rescinded what by their counsel he had formally pronounced.
The stars placed in the right hand of God are the souls of the saints, or, what is the same thing, the entire congregation of the blessed who have been and who will be until the consummation of the world. In a similar way, we have said that the seven lampstands are the one true church that has been established during the seven-day period of this world, which is founded by faith in the Trinity and which is made strong by the sacrament of the heavenly mystery.
The seven stars are the angels of the seven churches. That is, the rulers of the churches. For the priest, as Malachi says, is the angel of the Lord of hosts (Mal. II).
Now since he has made clear to him what the stars and what the lampstands are, he goes on to speak of the evidence against each of the churches. He explains to the blessed evangelist how he is to lay a charge against the church which strays far away from the divine purpose, and how he is to commend the carefulness of those who observe part of the evangelical law, while in other cases he is to set right those which are stumbling. Christ, “who wills all people to be saved” and wishes them to become heirs and partners of his own bounty, has ordered his word and teaching as an appropriate remedy for each of the churches, and has enjoined the evangelist to spread abroad the gospel and his teaching. To him be glory for ever and ever. Amen.
[AD 202] Irenaeus on Revelation 1:20