Chapter 11 — Part I: The Creed — Article IX: The Holy Catholic Church; the Communion of Saints
Section 32. Again, Optatus of Milevi says: You cannot be excused on the score of ignorance, knowing as you do that in the city of Rome the episcopal chair was first conferred on Peter, who occupied it as head of the Apostles; in order that in that one chair the unity of the Church might be preserved by all, and that the other Apostles might not claim each a chair for himself; so that now he who erects another in opposition to this single chair is a schismatic and a prevaricator.