Wherefore we ought to pray earnestly, and implore Almighty God with continual supplications, that He would avert this error from that man's soul, and remove this mischief of pride and confusion from the unity and humility of the Church. And with the favour of the Lord we ought to concur, and make provision with all our powers, lest in the poison of one expression the living members in the body of Christ should die. For, if this expression is suffered to be allowably used, the honour of all patriarchs is denied: and while he that is called Universal perishes per chance in his error, no bishop will be found to have remained in a state of truth.
It is for you then, firmly and without prejudice, to keep the Churches as you have received them, and not to let this attempt at a diabolical usurpation have any countenance from you. Stand firm; stand secure; presume not ever to issue or to receive writings with the falsity of the name Universal in them. Bid all the bishops subject to your care abstain from the defilement of this elation, that the Universal Church may acknowledge you as Patriarchs not only in good works but also in the authority of truth. But, if perchance adversity is the consequence, we ought to persist unanimously, and show even by dying that in case of harm to the generality we do not love anything of our own especially. Let us say with Paul, To me to live is Christ, and to die is gain. Let us hear what the first of all pastors says; If you suffer anything for righteousness' sake, happy are you. For believe me that the dignity which we have received for the preaching of the truth we shall more safely relinquish than retain in behalf of the same truth, should case of necessity require it. Finally, pray for me, as becomes your most dear Blessedness, that I may show forth in works what I am thus bold to say to you.
Source: Register of Letters (New Advent)