As for Eastern / Russian Orthodoxy's particular tenets, surely, discussion thereof would require a whole special thread, but I am not that knowledgeable and besides, I find myself driven more by existentially missionary concerns - how not to replicate a stale image of W.A.S.P. "chosen and frozen" type of religion in a context of a very good works oriented, non-theologizing, mystical religion, whose main and sometimes spoken motto has been - "don't tell me what you believe, - just show me how you pray..." In such a context, where culture expects almost a tangible holiness from a Christian professor, it is quite a challenge to live out (not just to confess) a sola scriptura witness...Because, ultimately, no one cares about my high grace predestinarianism, if my practical walk is laming on all fours...
That's the challenge.

For the truth's sake, which dwelleth in us, and shall be with us for ever (2Jn.1:2).