Neo wrote, "Christian unity isn't a common belief system; it isn't even a common belief in Christ! Christian unity arises from the fact that we share in common Christ himself, the same Christ indwelling each of us."
--"Salvation is not adherence to a 'belief system.' It is total trust, and abidance in Christ. Which, by definition, means also the Church; for to trust Jesus fully means we will fully trust and abide in His Body. Will this affect what and how I believe? Yes. Do we have to have our intellectual ducks in a row to 'be saved?' Nope."--
The point I labored to make then (poorly, it seems) and that I will continue to make is that doctrinal unity doesn't need to be striven for or created by us because it already exits in the Church. *Doctrinal agreement is a result of, not a prerequisite for, ontological and sacramental unity.*
In other words, the historic Christian way is that we experience, we live out, we incarnate the truth first, and *through that common experience* come to understand and agree on doctrine. Jesus said "Take eat," not "Take, understand, dissect, systematize, rationalize, deconstruct, recontextualize...then eat."
Orthodoxy, no matter what culture the Church is in, is a way of life that for those who follow it will result in a particular worldview, a common vision and experience. We see this in the lives of the saints and the Fathers across the centuries. We simply call this the "mind of Christ" as St. Paul does. For more on this, check out this article by Frederica Mathews-Green I quoted a few days ago.
Within in the Orthodox Church there are many different practices, pious opinions, and perspectives on a wide range of topics. But the difference is that nobody disagrees on what the Faith actually *is*, who God is, etc. This core is not the "disputable matters" of which St. Paul writes about in Rom 14:1.
But while common beliefs do not guarantee unity, a lack of them is a fruit, a sign, of ontological disunity no matter how unified things may seem on the surface. Thus the manifest divisions and contradictory theologies in western Christendom prove, not that we share a "common Christ" and thus are unified beneath our differences, but that we are not unified. The fact that we do not believe the same things about reality, while horrific, is actually just a symptom of a much more terrible disease: schism from the Church.
Ironically, it is western Christendom that most represents what we would call a "belief system"; i.e. a Matrix-esque construct divorced in various degrees from the full sacramental and ecclesial reality God has established. As Silouan writes, "An individual Christianity dissociated from the communities founded by the Apostles can not claim to be historically, organically, the same congregation (ecclesia) which was born at the outpouring of the Holy Spirit in Jerusalem on Pentecost. At best an individual, independent Christian or congregation can only claim to be an adherent to a belief system, or a para-Church organization."
This is why western Christians tend to always think of church almost exclusively in terms of "institutions", "programs", "models" etc. They have no real experience of Church as a living organism, a fully human AND fully divine living reality. Coupled with a repeated "either/or" perspective on the different paradoxes of faith instead of a more holistic "both/and" vision explains, in part, why Orthodox ecclesiology is so often misunderstood by the West.