Ok so the East is separated from the West based on doctrine. Thought so.
The Orthodox Church opposes the Roman doctrines of universal papal jurisdiction, papal infallibility, purgatory, and the Immaculate Conception precisely because they are untraditional."
- Orthodox apologist and author Clark Carlton: THE WAY: What Every Protestant Should Know About the Orthodox Church, 1997, p 135.
The Church preserves unity in diversity. In the Orthodox Church there is no hierarch with universal jurisdiction since its One True Shepherd, our Lord Jesus, has never left His Church (Matthew 28:20). The Apostle Peter does not replace or substitute for Him. The Scriptures do indeed indicate that Peter exercises an important role as leader among the Apostles but his primacy is exercised in equality or collegiality ("primus inter pares") as the Book of Acts clearly shows. The Rock upon which the Church is built is our Lord Himself as we proclaim during Matins: "The Stone which the builders rejected has become the Cornerstone; this is the Lord's doing and it is marvelous in our eyes" (from Psalm 118:2 - also the most often repeated phrase from the Old in the New Testament: Matthew 21:42, Mark 12:10, Luke 20:17, Acts 4:11 and 1 Peter 2:7). Peter, a leader among the Apostles, was first to proclaim the Church's faith in our Lord upon Whom it is built: "You are the the Christ (i.e. the Messiah, God's Chosen and Annointed One - igk), the Son of the Living God" (Matthew 16:15). He did not see himself as that Rock. Such, at any rate, is the conviction of the Orthodox Church. —
http://www.ukrainian-orthodoxy.org/questions/2007/appostolic.html
Roman Catholicism, unable to show a continuity of faith and in order to justify new doctrine, erected in the last century, a theory of "doctrinal development." Following the philosophical spirit of the time (and the lead of Cardinal Henry Newman), Roman Catholic theologians began to define and teach the idea that Christ only gave us an "original deposit" of faith, a "seed," which grew and matured through the centuries. The Holy Spirit, they said, amplified the Christian Faith as the Church moved into new circumstances and acquired other needs...
On this basis, theories such as the dogmas of "papal infallibility" and "the immaculate conception" of the Virgin Mary (about which we will say more) are justifiably presented to the Faithful as necessary to their salvation.
- ORTHODOXY AND ROMAN CATHOLICISM
Orthodoxy is not simply an alternative ecclesiastical structure to the Roman Catholic Church. The Orthodox Church presents a fundamentally different approach to theology, because She possesses a fundamentally different experience of Christ and life in Him. To put it bluntly, she knows a different Christ from that of the Roman Catholic Church.” —
Clark Carlton, THE WAY: What Every Protestant Should Know About the Orthodox Church, 1997; Paths & Polemics.
“because it has all the proper attributes, the Orthodox Church is the living realization of the One Holy Catholic and Apostolic Church.”
— An Orthodox Response to the Recent Roman Catholic Declaration on the Nature of the Church | Antiochian Orthodox Christian Archdiocese
Then there are those who attempt to join together all Christian religions into one faith. They would be horrified at the idea of a service with Hindus and Christians celebrating together, yet they do not bat an eyelash at the idea of Orthodox celebrating with Roman Catholics, who with no authority broke off from the Church close to a thousand years ago. —
Against Ecumenism
The feeling is mutual:
Few Catholics realize that Eastern Orthodoxy, especially as represented by Palamite theology, represents a systematic and comprehensive attack upon Catholic doctrine. Catholic and Orthodox theology are not only in opposition to one another in their understanding of God (theology), but also in the various disciplines of philosophy – in Cosmology, Psychology, Epistemology, Metaphysics, Theodicy, and Ethics. They posit radically different views of God, of man, and of the relationship between God and His creation... Over the past 2,000 years there have been many heresies, schisms, and systems of thought comprehensively opposed to Catholicism. But none has carried the potential threat for corruption of all of Catholic dogma which Eastern Orthodoxy represents.
— Part III: Eastern Orthodoxy: Never The Twain Should Meet – The War Against Being
