Evangelicals who interact with Orthodox--particularly converts TO Orthodoxy from Evangelicalism--have to put up with a lot. Specifically, they hear a refrain from us that "sola scriptura leads to doctrinal chaos!" and "Scripture plus tradition leads to wonderful doctrinal unity!" Now, while I personally agree with what we as Orthodox mean by all this, that's just sloppy apologetics on our part...it needs to be unpacked in more than just a sound byte, since Evangelicals reckon themselves to have just as much "unity in essentials" as the Orthodox claim to have.
For me, the difference lies in this: ecclesiology mattered desperately to the early Church, so much so that they put an article in the Creed that the Church was One, Holy, Catholic and Apostolic...that "One" part meaning that only one, visible communion would comprise it. Granted, it was never cut and dry which group it was when controversy came up, but the understanding was there--even among heretical groups of the first 300 years or so!--that groups which held to contradictory teachings on certain issues could not share the same chalice, and therefore could not both comprise the One Church.
So much is made of the fact that the Orthodox, being (as we see it) that One Church established by Christ, is doctrinally consistent. This is why the "Churches in Resistance" like the Athonite monasteries and Russian splinter groups that have broken communion with so-called "World Orthodoxy" ( i.e., the four historical patriarchates of Constantinople, Alexandria, Antioch, and Jerusalem and all those in communion with them) are either now themselves the One Church, or have separated themselves from the One Church. It's hard to tell until 20/20 hindsight clears things up (thanks being given to the Holy Spirit), but this sort of excommunication/reestablishment of communion is what has plagued/blessed the Church for 2,000 years. It's a "plague," for it's never pleasant--often, really, it's downright ugly and folks have lost it, calling folks all kinds of names they shouldn't have--but it's a blessing, overall, because these guys erred on the side of caution: they absolutely refused to believe that the Church could be divided on something that was seen as a major christological dogma and still be seen as "One."
Enter Evangelicalism, specifically (bear with me, those of you who read this blog who adhere to sola scriptura) those declaring sola scriptura to be their bond of unity. Well, all right, Christ is ultimately the bond of unity they claim, but you get me. Here we have groups that believe all kinds of different things re: baptism, the Eucharist, the nature of the Church, the nature of salvation, the means of acquiring said salvation, the operation of the Holy Spirit--even what it means to adhere to sola scriptura. Much could be made of the fact that the Early Church Fathers (hereafter ECFs) were absolutely unified on the nature of these issues--they were even more unified on these than they were regarding the canon of Scripture--but unity or disunity on this or that doctrine will only get an Orthodox and an Evangelical so far in a debate, in my experience.
It has been suggested that we Orthodox compare apples to apples and acknowledge that Southern Baptists (for example) have just as much unity amongst themselves as the Orthodox do amongst themselves (if not more, thanks to detailed systematic theology on the part of the Evangelical). Granted, readily. But this is not my problem with comparing the doctrinal cohesiveness of these two confessions. My problem is the fundamental difference between said confessions' respective beliefs regarding who or what constitutes the One Church of Christ. Whereas the Orthodox see the One Church of Christ as being necessarily doctrinally consistent on all declared matters of faith ("declared" being the key word here), and thus have no problem with Orthodoxy alone comprising the One Church, sola scriptura Evangelicals (it is my opinion--corrections are welcome) are satisfied with saying that groups can be diametrically opposed to each other regarding all the things I listed one paragraph above this one and still, as a group of contradicting confessions, comprise the One Church of Christ. If there's one thing that was made clear through my extensive readings of the ECFs (almost all Ante-Nicene authors), it was that, without exception, no one who did not hold to the Real Presence, Baptismal Regeneration, Infant Baptism, or Apostolic Succession (to name the most prominent four teachings that stand in opposition to most sola scriptura adherents' beliefs) could be said to be in the One Church of Christ, as these were seen to directly oppose the christology of the early Church.
In other words, for the statement that "Baptists have as much unity as Orthodox" to hold any water with an Orthodox Christian whatsoever, the one making said statement would also have to say that "Baptists alone constitute the One Church; they alone are the Body of Christ on Earth." The fact that (some) Lutherans, Church-of-Christers, Presbyterians, and Five-Pointers are included as members of the One Church along with Baptists is what drains the efficacy out of the whole argument. The One Church has more than One Faith in this latter version, it seems.
Still, many an Evangelical remains faithful to sola scriptura because he sees the controversies in Roman Catholicism and/or Orthodoxy as "the proof in the pudding" of their comparable fallibility--in a word, said Evangelical thought he was no worse off in Protestantism than he'd be in the Roman Catholic Church or Eastern Orthodox Church regarding doctrinal confusion, and, hey, at least he could unambiguously point to where his concrete, written-down (and leather-bound), rule of faith was....as opposed to trusting in a sometimes more nebulous "tradition"...
Whence, then, the Orthodox distinction betwen the disunity among the various groups identifying themselves with Orthodoxy and that sola scriptura adherents? In a nutshell, the issues sola scriptura folks disagree on are not only major doctrines in the Early Church, but also major doctrines that enjoyed universal accord among these ECFs. In contrast, the issues of Calendar and Reception of Converts in their current contexts were not directly dealt with by the ECFs, yet are seen by the "Synods in Resistance" in this day and age as major christological affronts, and thus threats to the doctrinal unity of the One Church. In their minds, separation is the only choice if doctrine is different.
God has seen fit to reconcile the Russian Church over the last couple of weeks. May the others who are taking these stands against what they see as false union enter into true (re)union with the rest of the world calling itself Orthodox, and--just as we have experienced for 2,000 years, let God be true; let His truth conquer all men's lies, regardless of what side of the conflict they came down on.