From God's Word:

Among the sedes apostolicae, there is in turn the sedes apostolica of Rome, which obviously relates to the other sedes apostolicae roughly as these do to the sees that are not directly apostolic. It thereby represents the ultimate and genuine criterion of Catholicity, sufficient in itself.

Taking everything together, we may determine that, at the moment when the theology of the successio apostolica  was first formulated as such, and when the Church first undertook to define her own nature, the "canon" of her being, in a conscious way, this theology was neither episcopal theology nor certainly papal theology; rather, it was dual, insofar as it distinguished between "episcopacy" and the sedes apostolicae--embodied, above all, in the one see of Rome. If the successio is the concrete form of the word, then that paramount--perhaps scandalous--concreteness that lies in the ultimate connection with the Roman line of succession, has been part of it from the beginning: at this point, all anonymity is abolished; the concrete name makes the inescapable demand that one take up a position; it is the most acute form of that extreme concreteness in which God set out by assuming, not just a name for men, but the flesh of man--the flesh of the Church. Must it not also be the most acute form of scandal that this "foolish" action of God provokes?

Let us return. It is clear that the duality of the earliest theology of succession afforded by the emphasis on the sedes apostolicae has nothing to do with the later concept of patriarchates, to which it may well have supplied starting points. Confusion of the original claim of the sedes apostolica with the administrative claim of the city that is a patriarchal see characterizes the tragedy of the dispute beginning between Constantinople and Rome. The concept of the patriarchate, which, especially from the Council of Chalcedon onward, was set in opposition to the Roman claim, and tried to contain it within the patriarchal way of thinking, misjudges the nature of this claim at its most profound level, since it is based on an entirely different principle. The patriarchal principle is post-Constantinian; its significance is administrative; and hence its practice is closely linked with political and geographical realities; in contrast with that, the Roman claim is understood on the basis of the originally theological theme of the sedes apostolica. To the same degree that [new Rome] which could not consider calling itself "apostolic") blurred the old idea of the sedes apostolica in favor [of] the patriarchal concept, old Rome reinforced its references to the completely different origin and character of its own authority.

This authority is in fact quite different from a primacy of honor among patriarchs, because it operates on a quite different level, independent of such administrative concepts. The concealing of the old theological idea of the sedes apostolica, which was after all from the outset a part of the Church's understanding of herself, by the idea of the five patriarchates must be regarded as the real evil in the dispute between East and West, an evil that also had its effect upon the West, inasmuch as--despite the retention fo the concept of the sedes apostolica--a largely administrative and patriarchal concept of the importance of the Roman See developed that could hardly help any outsider to have a clear grasp fo the real essence of the Roman claim, as distinct from any other claims. [33-35]

Pope Retires Title "Patriarch of West" as Obsolete
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