Consider, I pray thee, that in this rash presumption the peace of the whole Church is disturbed, and that it is in contradiction to the grace that is poured out on all in common; in which grace doubtless thou thyself wilt have power to grow so far as thou determinest with thyself to do so. And thou wilt become by so much the greater as thou restrainest thyself from the usurpation of a proud and foolish title: and thou wilt make advance in proportion as thou art not bent on arrogation by derogation of thy brethren. Wherefore, dearest brother, with all thy heart love humility, through which the concord of all the brethren and the unity of the holy universal Church may be preserved. Certainly the apostle Paul, when he heard some say, I am of Paul, I of Apollos, but I of Christ (1 Cor. 1:13), regarded with the utmost horror such dilaceration of the Lord’s body, whereby they were joining themselves, as it were, to other heads, and exclaimed, saying, Was Paul crucified for you? or were ye baptized in the name of Paul (ib.)? If then he shunned the subjecting of the members of Christ partially to certain heads, as if beside Christ, though this were to the apostles themselves, what wilt thou say to Christ, who is the Head of the universal Church, in the scrutiny of the last judgment, having attempted to put all his members under thyself by the appellation of Universal? Who, I ask, is proposed for imitation in this wrongful title but he who, despising the legions of angels constituted socially with himself, attempted to start up to an eminence of singularity, that he might seem to be under none and to be alone above all? Who even said, I will ascend into heaven, I will exalt my throne above the stars of heaven: I will sit upon the mount of the testament, in the sides of the North: I will ascend above the heights of the clouds; I will be like the most High (Isai. 14:13).
…Was it not the case, as your Fraternity knows, that the prelates of this Apostolic See, which by the providence of God I serve, had the honour offered them of being called universal by the venerable Council of Chalcedon. But yet not one of them has ever wished to be called by such a title, or seized upon this ill-advised name, lest if, in virtue of the rank of the pontificate, he took to himself the glory of singularity, he might seem to have denied it to all his brethren.
—Gregory the Great (c. 540–604), “Register of the Epistles of Saint Gregory the Great [5.18],” in Leo the Great, Gregory the Great, ed. Philip Schaff and Henry Wace, trans. James Barmby, vol. 12b, A Select Library of the Nicene and Post-Nicene Fathers of the Christian Church, Second Series (New York: Christian Literature Company, 1895), 166–69.