The "hand" that held the pen is an important aspect to consider in relation to the authority of scripture, but as you identified, it is by no means the only aspect. I offer a couple of observations concerning your comments if they might be helpful:
All of these points can be debated—and have been by academics. My point in mentioning them is simply to say that I do not believe the authorship of either Genesis or Revelation is as open-ended as you describe. Having said that, I also agree with your observation that identifying the author is not critical to recognizing the authority of the inspired text. It is merely one of several characteristics employed by the early church in recognizing the authority of the various books.
A resource I would recommend reading is Chapter 12 from Giesler and Nix A General Introduction to the Biblea. Perhaps there are some aspects of canonization they touch on that may be of interest.
Regarding your observation, Within the book of Revelation, the author is not identified:
This all depends upon how a person reads "John" in the context of the most prophetic revelation given since the book of Daniel. Some prefer to understand the lack of mention of "the apostle" as saying it could be "any John." I don't see it that way because I believe for a person to merely say "John," to be in Asia minor, to be writing to the seven churches at that historic time, and to have the greatest prophetic revelation of the entire NT guarantees it is none other than John the apostle. For it to be anyone else ignores the entire character of other significant prophetic revelation (e.g., Daniel, Isaiah, Ezekiel). To conclude that it is possible, or even likely that God gave Revelation through "another John" who happened to be alive during the same period, who is virtually unknown to the historical record, ministered in the same area, claimed to be on the same island that history witnessed the apostle John was banished to, never bothered to differentiate himself in the text from the most famous John of all history, and was unknown to the earliest Church Fathers is questionable logic.
In other words, what I'm saying is that those who hold to a non-apostolic authorship and appeal to the lack of "the apostle" in the text don't have much of a leg to stand on because that view elevates some fairly minor textual differences—which are explainable in other ways than another author—above the plain absurdity (my words) of having a mystery John show up out of nowhere, pen the greatest book of Revelation known to man, and disappear in the mists of history without any substantial trace.
Maybe I can illustrate my point in another way: To say that "within the book itself the author is not identified" is akin to saying that "within the book of Daniel the author is not identified." John says he is "John." Daniel says he is "Daniel." Does that mean that if it weren't for what Jesus happened to say in Mt 24:15; Mr 13:14 we wouldn't know who wrote Daniel? I don't accept this conclusion. You say that "John" in the context could be ANY John and therefore we don't know who really wrote it. I say that "John" in the context couldn't be ANY OTHER John and therefore we DO know who wrote it (especially when the testimony of the early church is factored in).
As for the authorship of Deuteronomy, it is easier to tie Deuteronomy to Moses than even Genesis. Deuteronomy (and Exodus) are cited throughout the (inspired) NT and, surely, in many spots attributed to "Moses." So arguing otherwise is to argue with inspired writers.
You mention the differences in style of the Greek in Revelation vs. John's gospel as evidence that Revelation was not written by John the Apostle. I am aware of these issues—which I discuss in the course and the commentary on Revelation: style of writingb and authorshipc which I would recommend reading.
Not everyone who is knowledgeable in Greek concurs with the interpretation of what those differences mean. We all recognize the differences, but are they so significant and difficult to explain (in other ways) to overthrow the weight of logic for apostolic authorship? Not for the betting man.
Here's where I'm coming from:
- The Greek is different to some degree. Experts disagree about whether it is significant or whether it reflects intentional violations of grammatical structure to purposefully carry across Hebraisms: the divine name, etc.
- For every "difference," there are also similarities which are unique to John's gospel and Revelation (Lamb of God, Word of God, overcomer, etc.).
- John doesn't say he is "the apostle" but history tells us he ministered in Asia minor at the right time and the earliest church fathers attributed the book to him. For any other John to simply say "John" is extremely presumptuous.
- The pattern of God is to give great Revelation to those who have great intimacy (e.g., Moses, Daniel). Who better in the NT than John the Apostle, the "disciple whom Jesus loved"?
For modern academics (some say "scholars") to overthrow church tradition and the simple obvious conclusion because of internal textual subtleties which are subject to various interpretations is not something I see as convincing. I think it is focusing the microscope on the flea and missing the elephant.
This is all part of a (dangerous) trend in modern scholarship to elevate after-the-fact assessment of internal evidence—which we discuss is highly subjective—over on-the-scene external evidence (e.g., the testimony of the early church). I see that simply as bad logic.
I guess part of what I'm reacting to—having spent years as a skeptic and in engineering school and disciplines—is how easily improper emphasis is placed on various pieces of evidence which, in turn, lead to questionable conclusions being elevated above more sound conclusions based on better evidence. In the case of the the authorship of Revelation (and many other NT books) I think this has become somewhat of an epidemic. Since this is "historic investigation" we can never be entirely dogmatic where we don't have all the facts. But, we CAN proceed like a court of law—and the best evidence should have the most weight. As a seminary student coming from an engineering background, I've been appalled by how often questionable subjective interpretation by moderns is allowed to run rough-shod over more objective evidence closer to the scene (e.g., historic testimony)—the exact opposite of what would happen in a court of law. So my comments in relation to the authorship of Revelation are partly in reaction to that.
There is another pattern I've seen: where there is a tendency and even desire to dismiss traditional apostolic authorship there is generally a drift toward liberalism and the elevation of academic theory over devotion and simplicity. I've seen this first-hand in colleagues who initially take seemingly small steps in this direction but eventually wind up undermining the authority of God's Word—all the while convinced they are serving our Lord. So that's my sensitivity.
Yes, it "could" be another John. But—based on what we know and biblical patterns—to give this possibility more than a passing thought is "bad logic." One man's opinion.