Book 20
10. […]Now, after it says, "Over these the second death has no power'', it goes on to say, ''but they shall be priests of God and of Christ, and they shall reign with him a thousand years” (Rev 20:6). Clearly, this does not refer only to bishops and presbyters, who are now properly called priests in the Church. Rather, just as we call all Christians ''christs” by virtue of their mystical anointing, so we call all Christian "priests” because they are all members of the one priest. That is why the apostle Peter says that they are ''a holy people, a royal priesthood” (1 Pet 2:9).
(trans. W. Babcock, slightly altered)