In many of the recent discussions here, Orthodox has made undocumented assertions about what is and isn't Tradition in Eastern Orthodoxy. If some belief that he disagrees with was popular at some point in church history, he'll tell us that such popularity doesn't prove that the belief in question should be accepted. He tells us that even something like a majority or 90% could be wrong. But if something he agrees with became popular at some point in church history, he'll claim that such popularity proves that we must accept such a widespread belief as Divinely guided.
In a recent discussion, he claimed that the popularity of ending the gospel of Mark at 16:8 in the earliest manuscripts is to be rejected. He suggested that a "prolific copier" might have gotten a bad copy of Mark, one that didn't include the right ending, and thereby distorted the early manuscript record by placing a lot of errant copies into circulation. But when the longer ending to Mark that Orthodox prefers is popular in the later manuscript record, he tells us that we must therefore accept that longer ending.
If Orthodox is correct in his assertion that his longer ending of Mark (as distinguished from other longer endings that circulated in ancient times) is Eastern Orthodox Tradition, then we would expect other Eastern Orthodox to be aware of that fact. That would especially be true of Eastern Orthodox scholars. And Orthodox has repeatedly told us that Eastern Orthodox don't have the sort of disunity we see among Protestants. Orthodox hasn't just criticized organizational disunity among Protestants (the fact that they belong to different churches or denominations). Rather, he's also criticized their differences in belief as unacceptable. Supposedly, then, there are no such disagreements among Eastern Orthodox.
In past discussions, Orthodox has even said that we can know the position of the Eastern Orthodox faith on an issue by asking any individual Eastern Orthodox about it. When I suggested to him that some Eastern Orthodox might be misrepresenting the Eastern Orthodox faith, he dismissed that objection as unreasonable and claimed that I should believe whatever he tells me about Eastern Orthodoxy, since he's Eastern Orthodox. He also told me, repeatedly, that it would be sufficient for me to consult a single Eastern Orthodox priest to get answers to any questions I have about what Eastern Orthodox believe.
In the recent discussion about Mark 16 linked above, I appealed to the work of Bruce Metzger, one of the foremost New Testament textual scholars of modern times. Orthodox tried to undermine my citations of Metzger by posting some quotes contained in a Reader's Digest Bible that Metzger was associated with. He apparently got the quotes from a King James Only web site. (See here.) According to Orthodox, it's unacceptable for Metzger to be associated with a Bible that even mentions the fact that a majority of modern scholars question the traditional authorship attribution of a Biblical book, for example. Even if Metzger doesn't support that scholarly opinion, he's to be faulted for even being associated with a Bible that mentions the existence of such scholarly opinion. As I explained to Orthodox, I don't accept all of the claims made in the quotes he provided from the Reader's Digest Bible, but I can disagree with Metzger or the people who worked with him on that Bible on some issues without accepting all of Orthodox's conclusions. But if Orthodox wants to hold Metzger and Protestants in general to the standard that he's suggested, then let's apply that same standard to Eastern Orthodoxy.
Since we keep getting undocumented assertions from Orthodox regarding what Eastern Orthodox believe, I thought it would be useful to quote the comments of some Eastern Orthodox scholars regarding issues like the ending of Mark's gospel and Biblical authorship. The examples below are representative of a much larger number of examples that could be cited.
In a work composed by some of the leading Eastern Orthodox scholars of our day, the Eastern Orthodox New Testament scholar Veselin Kesich wrote:
"The Gospel of Mark ends with the women fleeing from the tomb. They are in awe. There is no specific list of Christ's post-resurrection appearances in this gospel. The so-called 'longer ending' of Mark (16:9-20) is most probably a later composition, and our important ancient codices, the Codex Vaticanus and the Codex Sinaiticus, do not contain it." (in John Meyendorff, ed., The Primacy Of Peter [Crestwood, New York: St. Vladimir's Seminary Press, 1992], p. 37)
The Eastern Orthodox New Testament scholar and priest John Breck:
"St. Mark's Gospel seems originally to have ended with 16:8." (Longing For God [Crestwood, New York: St. Vladimir's Seminary Press, 2006], p. 48)
The Eastern Orthodox scholar and priest Paul Nadim Tarazi writes the following about the structure of the gospel of Mark. Notice where he ends:
"The literary structure of Mark can best be discerned precisely by paying attention to the way Paul and the issues facing his Gentile churches show through in the story of Jesus. The story is built around a framework that begins with a preamble (1:1-15) followed by three cycles of calling/invitation (1:16-3:12; 3:13-6:6a; 6:6b-8:21) and three cycles of teaching (8:27-9:29; 9:30-10:31; 10:32-45). Then there is a pivotal pericope  where Timothy's leadership as Paul's successor is introduced (10:46-52), and that is followed by two long sections, one offering the gospel for the last time to the Jerusalemite Christian leadership (chs.11-13) and one recounting their refusal of it (chs.14-15). Finally there is a short text indicating the door is still open for Peter and his following (16:1-8) to accept Paul's gospel." (source here)
Regarding the pericope involving the woman caught in adultery in John's gospel, a passage that Orthodox has also claimed we must accept, Tarazi writes:
"This pericope does not seem to have been part of the original text of John; it is omitted from many of the earliest and most reliable manuscripts." (The New Testament: Introduction, Volume 3: Johannine Writings [Crestwood, New York: St. Vladimir's Seminary Press, 2004], p. 181)
Below are some comments on other subjects from various Eastern Orthodox scholars. Some of these comments are on subjects I've discussed with Orthodox in the past.
"evidence that there was a single bishop leading the Roman church is lacking for that period [the first century]; indeed what evidence there is suggests a rather different picture. When Clement wrote to the Corinthian Church, he wrote not as bishop in the later sense but as one of the presbyters of the Roman Church entrusted with the task of writing on behalf of the whole Church to the erring Church of Corinth; similarly, Ignatius, writing perhaps a decade later to the Roman Church, does not seem to envisage a 'bishop of Rome', despite his enthusiasm for monepiscopacy." (Andrew Louth, ed., Eusebius, The History Of The Church From Christ To Constantine [New York, New York: Penguin Classics, 1989], pp. xxii-xxiii)
"Whether there were bishops, in the later sense of the word, as heads of local churches, is a question for which we have no evidence in the third period. But the role that James played at Jerusalem, after Peter had gone, was surely very comparable to the role bishops were to play later on: a lifelong and continuous place as leader of a local church, with a group of presbyters in support. James may not have been called a bishop, but he was in fact the first monarchical bishop of a local church." (Nicholas Koulomzine, in John Meyendorff, ed., The Primacy Of Peter [Crestwood, New York: St. Vladimir's Seminary Press, 1992], p. 28)
"This pattern, with the threefold ministry of bishops, priests, and deacons, was already established in some places by the end of the first century." (Timothy Ware, The Orthodox Church [New York, New York: Penguin Books, 1997], p. 13)
"Nevertheless, it might be pointed out, there was only one bishop of Constantinople. However, even this idea of 'one city—one bishop' is not the only way the Church has existed over the centuries. Despite the rosy and romantic picture given by early Christian historians such as Eusebius, of the apostles appointing single bishops in each geographical area (thereby enshrining a vision of Church history articulated in terms of the succession of bishops), historical reality is more complicated. Already the Apostle Paul, writing to the Roman Christians, indicates the existence of over half-a-dozen different Christian groups or house-churches, each with its own leader (see Romans 16), and this before any apostle had visited Rome. Several decades later, St. Ignatius of Antioch also knew of no single 'bishop' of Rome, although he was the earliest and most forceful advocate of monoepiscopacy (the claim that the Christian community in each place must gather around a single bishop). Likewise St. Justin in the mid-second century. And when St. Irenaeus described the succession of the presbyters or bishops (he uses the term interchangeably) of the Christian community in Rome, it was the succession of but one of the communities, albeit the one that gradually assumed leadership over the others. All this is to say, there was no single bishop of Rome until the end of the second century, or perhaps even as late as the third decade of the third century. Instead, there were a number of churches, each led by its own bishop/presbyter." (John Behr, here)
"To make literal inerrancy a necessary component of the gift of inspiration is, after all, foreign to the New Testament message itself. The gospels bear witness to the Truth and to the power of God, not to their own freedom from error. They are free from falsehood or deception, but not from natural human errors. The evangelist Mark, for example, maintains that Abiathar was high priest during the reign of David (Mk 2:23-28), but according to I Sam 21:1-6, Ahimelech, not Abiathar, was high priest. This 'error' had no effect on the meaning of the passage. The concept of inerrancy conflicts with the incarnational approach to the Bible, and with the New Testament concept of the synergetic activity of the Holy Spirit. The charisma of inspiration does not imply a new revelation which transports its recipient into a sphere entirely different from his own. The concept of inerrancy reveals more about our desire for absolute certainty than it does about the inspiration of a biblical book." (Veselin Kesich, The Gospel Image Of Christ [Crestwood, New York: St. Vladimir's Seminary Press, 1992], p. 69)
"The most likely conclusion is that Daniel was written at a relatively late date, not just accepted into the canon late....Typically an apocalypse's author attempts to make it sound as though it was written in a previous age, forecasting as if they were future events things actually happening in the present for the book's author." (Paul Nadim Tarazi, The Old Testament: Introduction, Volume 2: Prophetic Traditions [Crestwood, New York: St. Vladimir's Seminary Press, 1991], p. 207, n. 3 on p. 208)
"the books of Daniel and Baruch may have been composed as late as the second century B.C....From the standpoint of the Orthodox Church, 'the entire Bible is inspired by God,' and this means that it 'contains no formal errors or inner contradictions concerning the relationship between God and the world.' The overall message of the Bible, that mankind has fallen under satanic bondage and that God has graciously acted in and through Christ to save us from that bondage, is infallibly true. According to the Orthodox doctrine of infallibility, the Church as a whole is the guardian of 'the eternal spiritual and doctrinal message of God' and is protected from error by the Holy Spirit. The Bible, therefore, as a testimony and proclamation of the Church concerning God's revealed plan of salvation, is without error in its central theological themes and affirmations. It is not necessary, however, for the Orthodox Christian to insist upon the literal truth of every statement contained in Holy Scripture. Many Orthodox scholars believe that the Bible may contain 'incidental inaccuracies of a non-essential character.'...But these kinds of historical and scientific inaccuracies do not undermine the coherence and validity of the essential theological message of Holy Scripture. The Orthodox Church, in affirming the divine inspiration and infallibility of the Holy Bible, does not exclude the possibility that the Bible might contain some minor errors of fact, but she insists upon the absolute truth of scripture's overall message of salvation." (George Cronk, The Message Of The Bible [Crestwood, New York: St. Vladimir's Seminary Press, 1982], pp. 18, 21-22)
"As Fr. Georges Florovsky commented (in his article 'The Boundaries of the Church'), St. Cyprian was right to affirm that salvation resides only within the Church, but 'he defined this in too hastily and too narrowly.' The designation of such people as 'schismatics' clearly indicates that this situation is not considered normal, and that their reunion with the bishop is desired; but that St. Basil can affirm that they are 'of the Church' is an important reminder that the Church is broader than those united with the bishop, and includes all those baptized in the right faith (even if schismatic)." (John Behr, here)