altogether myself and my writings, now and hereafter.'[1]
6. Clement VI., in 1351, writing to the Armenian Patriarch, says: 'If thou hast believed, and dost still believe, that the Roman Pontiff alone, when doubts arise concerning the Catholic Faith, can by an authentic determination, to which we must inviolably adhere, make an end of them; and that whatsoever he, by the authority of the Keys delivered to him by Christ, determines as true, is true and Catholic; and what he determines to be false and heretical is so to be regarded.'[2] Clement here plainly requires the Armenians to believe the infallibility of the Roman Pontiff as a truth of revelation.
7. It would be endless to quote from S. Thomas, but these few words will suffice: 'Therefore the Lord said to Peter, whom He made Supreme Pontiff, "I have prayed for thee, Peter, that thy faith fail not, and thou, when thou art converted, confirm thy brethren." And of this the reason is, that the faith of the whole Church must be One … which cannot so be kept unless questions of faith be determined by him who presides over the whole Church; so that his sentence be held firmly by the whole Church.'[3] And again: 'And while in other parts there is either no faith, or it is mingled with many errors, the Church of Peter both is fresh in faith and pure from error: and no wonder, because the Lord said, "I have prayed for thee, Peter, that thy faith fail not."'[4]
