Eastern Orthodox – Roman Catholic theological differences

The Roman Catholic Church and the Eastern Orthodox Church have been in a state of official schism from one another since the events of 1054—the East–West Schism. The causes of this breach were centuries in the making and stemmed to a considerable extent from cultural and political factors derived from the increasing isolation of the Latin scholarly culture of the West and the Greek scholarly culture of the Byzantine Empire. Historically, it has been argued that there are substantive theological differences between the Western and Eastern churches that have proven enduring points of contention.

Since the Second Vatican Council, the Catholic Church has generally taken the approach that the schism is primarily ecclesiological in nature, that the doctrinal teachings of the Eastern Orthodox churches are generally sound (with the exception of their understanding of papal primacy, the filioque clause, and the purification after death) and that "the vision of the full communion to be sought is that of unity in legitimate diversity" as before the division, since "the first councils are an eloquent witness to this enduring unity in diversity". In this view, the primary difficulty is disagreement on the role of the Pope.

Jeffrey D. Finch claims that "the future of East–West rapprochement appears to be overcoming the modern polemics of neo-scholasticism and neo-Palamism".

The administration of the Roman Empire was constituted by a predominantly Greek speaking Eastern half and a Latin speaking Western half. This linguistic division over time led to an administrative division of the two regions under the Emperor Diocletian in AD 285 and then to a separation into two empires: The Western Empire and the Eastern Empire (also known as the Byzantine Empire or Byzantium) with the passing of Theodosius I in AD 395. Theodosius I had established Nicene Christianity as the state religion of the Roman Empire. The Western Empire is generally said to have come to an end in AD 476, when Odoacer deposed Romulus Augustulus. By then, the whole of what had been the western part of the empire was ruled by Germanic invaders: Italy by Odoacer, Northern Africa, Sicily, Sardinia, Corsica and the Balearic Islands by Vandals, the Iberian peninsula by Visigoths, Roman Gaul by other groups, of whom the Franks were destined to become the most important, and Roman Britain by Britons and Anglo-Saxons. The Roman Empire, now ruled from Constantinople, never more than partially and temporarily recovered this area. The subsequent mutual alienation of the Greek-speaking East and the Latin-speaking West (leading to a stagnation in scholarly intercourse between the two cultures) led to increasing ignorance of the theological and ecclesiological developments of each tradition.

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Wikipedia