Consider Bruce Metzger's outline of the problem of the canon:
The recognition of the canonical status of the several books of the New Testament was the result of a long and gradual process, in the course of which certain writings, regarded as authoritative, were separated from a much larger body of early Christian literature. Although this was one of the most important developments in the thought and practice of the early Church, history is virtually silent as to how, when, and by whom it was brought about. Nothing is more amazing in the annals of the Christian Church than the absence of detailed accounts of so significant a process. (The Canon of the New Testament, 1987, p. 1)
Thus even standard accounts of the history of the canon admit a
paradox at the heart of it: the canon is both a fixed, "closed" set of texts, and a set of texts that, by the light of historical knowledge, has never been fixed as the canon, the Holy Bible, the authoritative scripture for Christians. Metzger tries to split the baby by concluding that the canon is open in theory, but in practice it is closed. That's awkward.
The paradox takes various forms. It appears that by the 4th century, as in Athanasius' 39th letter, our 27-book NT was actually fixed. But, as already observed in this thread, different churches and patriarchates and councils drew up different canonical lists well into the medieval era. Likewise, the modern NT draws upon 3 different text-types: the Alexandrian, the Western, and the Byzantine, none of which by itself is thought to be canonical. Again, for Metzger and others, it is not even clear whether "the NT Canon" means "a collection of authoritative books," or "an authoritative collection of books." The
open canon concept seems to correspond to the former, while the
closed canon concept characterizes the latter.
As suggested by my OP, I am proposing instead a deflationary understanding of "the canon," i.e. that it ain't what it is traditionally cracked up to be. Three books in particular are relevant to this argument: Trobisch's
The First Edition of the New Testament (2000), David L. Dungan's
Constantine's Bible: Politics and the Making of the New Testament (2007), and Charles Freeman's
A.D. 381: Heretics, Pagans, and the Dawn of the Monotheistic State (2008).
The theory is that two historical events are sufficient to explain the formation of the Christian Bible as the sacred text that we know today, rendering the standard modern accounts of "the Canon" unnecessary and obsolete:
(1) The 2nd century publication of the first edition, what Trobisch calls the "Canonical Edition," as simply a book, i.e., a codex anthology that could be bought and sold, copied and shared, read publicly or privately, as with any ordinary book. This remarkable codex anthology consisted of two parts, titled "Old Testament" and "New Testament," and was the unique archetype of today's Holy Bible. This was a discrete event, not a "gradual process," as per the dominant theory.
(2) The 4th century political and legal establishment of Nicene Christianity as the unique state religion, first imperially sponsored by Constantine and his successors, and then imperially mandated and imposed by Theodosius I and his successors, for the entire Roman empire (and later its successor kingdoms). An essential component of this process was the legal and financial support given by the emperors to the Christian bishops to exercise their functions in large, opulent, well-funded basilicas and other buildings, in which the Christian scriptures were to be read publicly and revered. The commission by Constantine himself given to Eusebius of Caesarea in 332 to produce 50 copies of the scriptures for use in his newly endowed churches in Constantinople is a known and critical moment in this 4th century development, as is Pope Damasus' commission to Jerome in 382 to produce the Latin Vulgate edition of the Bible.
The first of these events is rather punctual and immediate, a true event: when the first edition was published. The second event is a long process that was only set in motion in the 4th century, and required a millennium to take full effect. Over the course of the middle ages, the Vulgate and the Byzantine "majority" text eclipsed local and eccentric canons, and became for modern Europe the "Holy Bible." It was only after the Reformation that it made sense to ask what "the canon" of scripture is or must be. Thus the Bible is a historical product of the late Roman Empire and its long medieval aftermath, not the result of any deliberate debate or decision by any church.
I think that this understanding of the formation of the New Testament, made possible by Trobisch's remarkable evidence-based demonstration of the 2nd century origins of the NT text, resolves the paradox in modern conceptions of the canon, such as Metzger's. The creation of the NT as book was not the same event as the sanctification of it as Canon or Holy Bible. The latter was a result of the contingencies of empire and the medieval evolution of Christianity. But together these events resulted in a fixed holy bible that was never formally closed in the pre-Reformation era.