Pope Gregory was concerned that the Patriarch of Constantinople, St. John the Faster, had accepted the title of Ecumenical (or Universal) Patriarch. He condemned any such title for the following reasons:
First, anyone who would use such a title would have fallen into pride, equal to the anti-Christ. He wrote: “I say it without the least hesitation, whoever calls himself the universal bishop, or desires this title, is by his pride, the precursor of anti-Christ, because he thus attempts to raise himself above the others. The error into which he falls springs from pride equal to that of anti-Christ; for as that wicked one wished to be regarded as exalted above other men, like a god, so likewise whoever would call himself sole bishop exalteth himself above others” (Ibid., 226).
Second, St. Gregory believed that such a title would be perilous to the Church. “It cannot be denied that if any one bishop be called universal, all the Church crumbles if that universal one fall” (Ibid., p. 223).
It is illuminating to understand that even some very illustrious Roman Catholic theologians today recognize that the Papacy as it now exists is of late origin. W. DeVries admits,
“...throughout the first ten centuries Rome never claimed to have been granted its preferred position of jurisdiction as an explicit privilege” (Orthodoxy, Roman Catholicism and Anglicanism by Methodios Fouyas, p. 70).
Avery Dulles considers the development of the Papacy to be an historical accident. “The strong centralization in modern Catholicism is due to historical accident. It has been shaped in part by the homogeneous culture of medieval Europe and by the dominance of Rome, with its rich heritage of classical culture and legal organization” (Models of the Church by Avery Dulles, p. 200) http://www.orthodoxresearchinstitute.org/articles/ecumenical/maxwell_peter.htm
Also, Archbishop Roland Minnerath, who was a contributor to the Vatican’s 1989 Historical and Theological Symposium, which was directed by the Vatican’s Pontifical Committee for Historical Sciences, at the request of the then Cardinal Ratzinger’s Congregation for the Doctrine of the Faith, on the theme: “The Primacy of the Bishop of Rome in the First Millennium: Research and Evidence,” states,
"Recent research on the Reformation entitles us to sharpen it and say that the Reformation began because the reformers were too catholic in the midst of a church that had forgotten its catholicity..."
“...To prepare books like the Magdeburg Centuries they combed the libraries and came up with a remarkable catalogue of protesting catholics and evangelical catholics, all to lend support to the insistence that the Protestant position was, in the best sense, a catholic position.
Additional support for this insistence comes from the attitude of the reformers toward the creeds and dogmas of the ancient catholic church. The reformers retained and cherished the doctrine of the Trinity and the doctrine of the two natures in Christ which had developed in the first five centuries of the church….”
“If we keep in mind how variegated medieval catholicism was, the legitimacy of the reformers' claim to catholicity becomes clear. (Pelikan, pp. 46-47).
"Substantiation for this understanding of the gospel came principally from the Scriptures, but whenever they could, the reformers also quoted the fathers of the catholic church. There was more to quote than their Roman opponents found comfortable." (Pelikan 48-49).
However, Scripture, tradition and history can only assuredly consist of and mean what Rome may say they do, and which is the real basis for the veracity of Rome for a RC. Thus no less than Cardinal Manning stated,
"It was the charge of the Reformers that the Catholic doctrines were not primitive, and their pretension was to revert to antiquity. But the appeal to antiquity is both a treason and a heresy. It is a treason because it rejects the Divine voice of the Church at this hour, and a heresy because it denies that voice to be Divine....The only Divine evidence to us of what was primitive is the witness and voice of the Church at this hour." — Most Rev. Dr. Henry Edward Cardinal Manning, Lord Archbishop of Westminster, The Temporal Mission of the Holy Ghost: Or Reason and Revelation (New York: J.P. Kenedy & Sons, originally written 1865, pp. 227,28