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Thanks for the very interesting comments and questions. I have looked at a lot of the possible natural divisions of the third Cycle, and am familiar with the one you propose. Yes, it makes some sense, but there is another possibility that seems more natural to me, and which is strongly confirmed by correlation with the other Cycles on the Wheel. If we accept the tradition that Hebrews was written by Paul, then we find a consistent pattern across all three Cycles:
I discuss this at length in Chapter 6 of the Bible Wheel book (available online here).
And here is an image of how these divisions align on the Bible Wheel. Note that the "Post-Exilic" OT books (the history after Israel was "scattered" during the Babylonian Exile) align with the three Epistles to the Scattered (to who both James and Peter addressed their letters).
Now any division of the 22 Epistles will be subject to dispute because there are unknowns. In the case of the division I have suggested, the only unknown is the authorship of Hebrews. But given that there is a strong tradition of Pauline authorship and the pattern strongly corresponds with the other divisions of the other Cycles, I am inclined to think it best.
I do see some support for the pattern you suggest. The move from "grace" towards "works" makes some sense, and it has a nice symmetry. But there are some problems with the pattern you suggest. First, the group you call "Letters written to Leaders" is not a standard group. Normally, the first three letters of that group are taken as their own group called the Pastoral Epistles because they were written to pastors Timothy and Titus. Second, the group you call "Letters written to seasoned Jew believers" was invented by the Dispensationalists who invented the doctrine of "two distinct peoples of God" (Christians and Israelites), and who say that the letters to the Jews don't even apply to Christians. It is a very recent innovation without any valid support from the text as far as I can tell.
Neither can I accept your assertion that "Revelations is understood more clearly by Christian Jews since it is so deeply embedded with Old Testament Symbolism." First, there is no book called "Revelations" (excuse me, but that's a pet peeve of mine). Second, there is absolutely no validity to the idea that the ability to understand the OT Symbolism is genetically or culturally based upon being Jewish. People who understand the OT do so because they have STUDIED it. And besides, many "Jewish Christians" have rejected traditional Christian doctrine such as the Trinity and the freedom from the Law because of their devotion to OT practices and a failure to understand how the church fulfilled prophecy.
Also, it seems clear that the third Cycle was not meant to have strong divisions like the first two because this way we have a total of seven perfectly symmetrical divisions which form the pattern of the tri-radiant halo of Christ seen in ancient Christian iconography:
The Canon Wheel ........... Icon of Christ
I talk about this in my article The Tri-Radiant Halo as the Sign of Deity.
Now if we added divisions to the third Cycle, we would destroy the sevenfold pattern which simply "falls out" from the traditional divisions. I have reviewed the levels of divisions in this article where I discuss the Complete Categorical View of the Bible. As you can see, the subdivisions on Cycle 3, no matter how you cut it, are very deep on Level 4 (furtherest to the right). The groups displayed on the Canon Wheel are from Levels 2 and 3. Note that all the divisions exist in the literature. I didn't have to "make up" any non-standard divisions.
You asked "Does this make sense? does it serve a purpose? or did I just ruin the whole bible wheel pattern?" Yes, it makes some sense, but it doesn't fit very well with the rest of the pattern whereas the traditional divisions fit very well. And yes, it does server a purpose, but it looks like that purpose is to support Dispensational theology which I think is fundamentally flawed and unbiblical. Finally, no, you did not "ruin" the pattern. You merely suggested a pattern that doesn't really fit that well with the rest. But it doesn't "ruin" anything.
Here's an image of the symmetries that I produced many years ago for my article Symmetries on the Bible Wheel where I discuss a number of sub-patterns:
Thanks again for your very stimulating questions! And don't worry - I don't think I have the "last word" on this. I merely answered your questions to the best of my ability.
It's really nice to have someone stop by to ask questions about the Bible Wheel and to suggest alternatives.