The proper term is "schism."
Defined: the formal separation of a church into two churches or the secession of a group owing to doctrinal and other differences.
___________________Think: GB vs Apostates___________
In 1054, the only true Universal Christian Church (in their opinion, of course) began a serious dispute with hard feelings on both sides which eventually resulted in a split because of geographic LOCATION, disputes on DOCTRINE, and AUTHORITY issues.
To put it in JW terms, they disfellowshipped each other's leaders and representatives, back and forth over many years.
Technically speaking, an argument can be made there was no institutional schism, only personal vendettas and petty retaliations.
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I won't go into all the details because, if you're interested, you can find them and read them elsewhere.
I sought the Catholic version of events:
http://www.catholic.com/tracts/eastern-orthodoxy
Then, I let the Orthodox side tell me their side of things:
https://oca.org/questions/romancatholicism/validity-of-roman-catholic-orders
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Suffice it to say, the Orthodox "Patriarch" and the Latin "Pope", both are words for Papa or Big Church Daddy, often got on each other's last nerve.
The schism sort of officially came only 60 years before the Protestant Reformation.
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Where does this leave us?
The Eastern Orthodox version of Christianity with its Patriarch was constantly battling with the Muslims and later the Czar of Russia until it fragmented along National lines.
Latin Catholics with their Pope, battled with Protestants.
Bottom line?
The Orthodox Church has 11 versions of the "Truth."
Latin Catholics split into Protestants (apostate Catholics) with thousands of splinter denominations vs. Papal-loyal loyalists.
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Are you still with me? Okay, let's continue. . .
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What are the points of contention between these groups, generally speaking?
1. Orthodox say Holy Spirit comes directly from the FATHER.
2. Catholics believe Holy Spirit comes from Father and Son
3. Orthodox say ONLY the first 7 councils were valid in creating and affirming true doctrine.
4. Catholics say the first 7 PLUS all the subsequent ones are equally binding.
5. Orthodox say the Pope is only the 1st among MANY true church leaders and not the sole authority with infallibility.
6. Catholics claim Peter was singled out as the 1st singular leader in charge of Heaven and Hell, but disciples had lesser roles to carry out.
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In 1965, the respective leaders of Orthodox and Catholic LIFTED the EXCOMMUNICATIONS (or, in JW terms, "Reinstated") each other.
This didn't amount to much more than window-dressing, however.
Yesterday, in Havana, the two leaders (Pope and Patriarch) sought to amend the ideological rift to mutual advantage.
What do they have to fight over now?
"Catholic clergy are celibate while Eastern or Orthodox clergy are allowed to marry. The churches also differ in the practice of the eucharist or communion ritual. The Roman Catholic Church uses unleavened bread for the communion host, while the Orthodox churches use leavened bread." (NPR http://www.npr.org/sections/parallels/2016/02/12/466395400/will-cuba-meeting-of-pope-and-patriarch-help-heal-a-1-000-year-rift)
WHAT IS THE BOTTOM LINE?
Obviously, to be a meaningful healing of the "wound," there would need to be a sharing of authority. This is the rough equivalent of the Governing Body of Jehovah's Witnesses meeting with a designated leader of Apostates and trying to find a way to mend fences.
IN OTHER WORDS: THERE IS NO WAY IT CAN HAPPEN!
Why would such an event take place in the first place?
I would offer only one explanation: "It makes both sides look like they are willing to forgive and forget--and this only for public consumption."
Importantly too, "The Catholic side wants to appear inclusive and Christ-like, while the Orthodox do not wish to appear to be insubordinate and entrenched, or petty."
The Pope doesn't want to be seen as a bully, the Patriarch wants to be seen standing beside the most powerful religious leader on Earth to elevate his status in the eyes of others.
When an aggrieved JW writes a letter to Headquarters or places a phone call, there is a public relations aspect to the protocol. Headquarters must APPEAR to be humble, willing to listen, reasonable, and even-tempered in addressing concerns.
Would the Governing Body bend to the requests of the Royal Commission?
Not really--they only want to appear to be willing and reasonable. No genuine changes are possible due to all vested interests in WHO IS IN CHARGE and WHO WEILDS AUTHORITY.
That is the bottom line, imho.
I'd like to hear your views.