John Karmiris: “The Ecclesiology of the Three Hierarchs,”

.......The mystery of the Church . . . is accepted by Christians on faith, and for this reason was included in the ninth article of our holy Creed as an object of faith, following directly the confession of our faith in the Father, the Son, and the
Holy Spirit. That is, since the Church traces its origin and creation to the one Triadic, true God, being united with the Son and having the Holy Spirit as its soul, which effects the salvation of men in and through the Church, with good
reason did the holy Fathers of the second Ecumenical Synod, among them Saint Gregory, ‘Spokesman of the Divine’ (theologos) . . . ordain that Christians confess their faith first in the Father, the Son, and the Holy Spirit, and immediately thereafter in ‘one, holy, catholic, and apostolic Church,’ in the sense that it is the very body of Christ, or the mystery of Christ which is perpetuated in history,
or rather Christ Himself, Who exists eternally in the bosom of the Father and Who, when the time had fully come, became man and is ever with us and lives and acts and saves and extends into the ages, and to Whom, therefore, the faith
of Christians refers, indirectly through the Church.