Well, I don't say that the Roman church emerged in the 300s; I acknowledge it existed before then...
But as the excerpt below points out...there was essentially one church til the time of Augustine...yet many strains...Eastern orthodox...the Roman church...the coptic church in Egypt & thereabouts...the Nestorian church...on the fringes...
A sort of diversity within semi-unity...
But if you're going to call it the ROMAN church...then that means you're talking about the church as centered in ROME...and the quote below shows you that other segments of the church simply didn't acknowledge Rome's authority til later...if even then!
The Roman Catholic church of today is not the church of Jesus, neither is it "catholic." The word "catholic" means universal and it is far from being universal. In the early church, until the time of Augustine, there was basically one church, which was universal, which was not centered in Rome. When the Roman bishops began to claim supremacy about the middle of the first millenium, the rest of the church did not agree. The church in Egypt, the Coptic Church, is more ancient than the Roman church and it has never been part of the Roman church. The Nestorian Church (the Eastern Church now found primarily in Syria and Jordan) has a history that is much older than the Roman church. The Orthodox Church also has origins that predate the Roman Church. There are many Christian groups that existed before the Roman church and continue to this day. The Roman church, with a strong bishop who claimed supremacy, was a late edition to Christianity, in the time-table of the church. Most of the Christian world rejected the Roman bishop's claim.
Source: A Short Summary of the History of Christianity
It's interesting that the author you cite refers his questioner to the Fathers but neglects to mention the Fathers who disprove his assertion that Roman authority didn't emerge until the 500s. For example, Irenaeus tells us (paragraph 3) that Rome handled a matter of dissension among the Corinthians. Clement, about the year 96, asserts his authority (paragraph 59). There are other sources prior to the middle of the first millenium that acknowledge the authority of the Bishop of Rome.
That said, I agree that there was dissension in some communities. Not everyone neatly lined up behind Rome. A refusal to obey Rome, however, doesn't make Roman authority a new invention around the 500s.
Peace be with you.
Err.. sorry, what are you talking about?
St. Augustine lived from 354 to 430 AD - this was 600 years before the schism and there was no differentiator Eastern Orthodox or Catholic.
Even the Coptic Church didn't have a schism until 450, which was after Augustine and Nestorius didn't propound his ideas until 435 --> so your statement is historically inaccurate
The church in Egypt, the Coptic Church, is more ancient than the Roman church and it has never been part of the Roman church. The Nestorian Church (the Eastern Church now found primarily in Syria and Jordan) has a history that is much older than the Roman church -- both of these are incorrect.
You conflate the Church of Alexandria with the Coptic Church and vice-versa.
Now the original Pentarchy of Churches -- the original 5 Churches were: Rome, Constantinople, Alexandria, Antioch and Jerusalem
All are equally ancient (except for antioch and jerusalem of course) -- you cannot say the Church in alexandria is older than the one in rome or vice-versa
The Church in Jerusalem is of course the oldest by a few years
The Church in Antioch was perhaps older by a year or more or less the same time -- remember that the Apostles went to preach to Jewish communities and there were Jewish communities in Rome as well as in Antioch
The Nestorian Church -- btw, there is and was no "Nestorian Church" -- it's a misnomer. There is the Church of the East that split from the Antiochene See and was and is based in Ctesiphon in Mesopotamia, but that has the doctrines of Babai the Great, not Nestorius
In any case, they moved from the overall Catholic Church in 440 to 450 and that was exacerbated by the politics that they were Christians in the Persian Empire -- as an aside to give you some historical background, the Church had spread well in Persia during the times before Constantine. But when Theodosius declared Christianity as state religion, the Persians saw this as a danger signal -- a fourth column among them, so started the persecutions
But, with this "Nestorius", the Persians saw a chance to split their Christians away from the Roman Christians
possibly the Church of the East saw this as a way to live in peace
yet note that the beliefs in the Eucharist etc. remain even in the Church of the East
The Sassanid Shahenshah took the theological discussion as a chance to politically divide the Church. Yet the beliefs as propounded by Babai the Great are Chalcedonic