This is not a common topic for me, but I was recently exposed to "Rightly Dividing the Gospel" through a friend. Although I'm what might be called "well read", and have a varied background in Christian religion, this was new.
Raised as a Fundamentalist Baptist in a small association called "The General Association of Regular Baptists" in N Wisconsin; doing a good deal of study on the history of world religions during and after college; eventually finding a home in Lutheranism (although Catholicism might well be even closer to my thoughts); being exposed to a small sect called "Apostolic Christian" which has something on the order of 30K members in the US, ... plus reading a lot of books, and articles on religion, but I'd never run into the "rightly divided gospel" slant.
My first reaction when I see something like this -- in religion, in "get rich quick schemes", in "did you know that xxxx is a huge conspiracy"?, etc, etc is to try to be gentle. All humans want to be "special", and to have "special knowledge" -- Birthers, Truthers (9-11 was an inside job), Pierre Salinger Flight 800, The Da Vinci Code, etc, etc ad nauseum. Most all of us have been taken in by more than one, and have some sympathy for some others. Human nature LOVES "special knowledge", and while REAL "special knowledge" is very hard to get, taking years of study and effort, the kind we all like is ALWAYS easy -- "everyone else just missed it!". (that is a big clue to falseness)
There is a special name for special knowledge related to Christianity "Gnosticism" ...the specific version where the physical world is created by a "demiurge" is only one example. The concept of "special knowledge" permeates Zoroastrianism, Neoplatonism and everything up through Mormonism and New Age cults. Folks have been at this a LONG time.
So the first test is "is this REALLY something that has been around a LONG time (stood the test of time), and who are the smartest people that support it?". Who founded it?, when did they do it?, what is their character?, what were their credentials?, etc.
So now I'll be a bit flip -- since I have acknowledged that we all have this weakness.
....and Christ said“Upon this Brock (Robert C Brock)I will found my Church … in 1985, and here is it’s “Vatican”… or for MO Synod, “Holy City” (St. Louis).
Not all that impressive. Google and "Street View" take some of the cachet out of such things.
The "core" of this "faith" is that God sent Paul to Gentiles and Jesus to the Jews, so "Gentiles" can just listen to Paul. This is more than a bit hard to take seriously right off the bat -- so did Christ die only for the Jews? Even for God, big time actions are pretty hard to ignore -- like dying for the sins of ALL.
I could spend time going through each of the verses they take out of context to attempt to make their case, but I'm not wasting my time. A cursory search of the web didn't show that anyone with any stature has even found this blip worthy of rebuttal, so I'm not inclined to tilt at the windmill Don Quixote style.
Humans love fixation. Lutherans tend to be fixated on "Grace" -- if there is anything that is required of them for salvation they get testy. Taking regular communion, darkening the church door, forgiving little of others since MUCH has been forgiven for them, any sort of "work", etc, they balk -- it must ALL be GRACE! Thus saith Luther -- but not Christ IMHO.
Baptists are all decisions and don'ts (don't drink, don't smoke, don't play cards, don't go to movies, don't dance ... it varies, but ye shall know them cuz they don't!
Catholics are just Catholic -- you are or you aren't. They have the "one true church founded on Peter" verse to lean on, and as someone who cares about history, their claim resonates with me.
But -- Christ resonates more. I'm never going to be a "Paulist", I'm a CHRISTIAN!!! Christ not only spoke and speaks to me, he DIED for ME (and I'm not a Jew). The actions of almighty God seep through time and space -- as well as his words. TO ME!
Paul is great -- he has his problems with women, getting married and of course "his thorn". He is fine, but he isn't GOD, and certainly not the SAVIOR!
Heresy is an old and new problem just like other temptation, and it always be as long as some guy in the corner hands out a pamphlet giving you "the secret knowledge". So we have the the Apostles Creed (180 or so), the Nicene Creed (325), and the Athanasian Creed (1642, But mostly from St Augustine, "On the Trinity" from 415). Not exactly "new knowledge".
We Lutherans may have gotten fixated on Grace (a very good thing in general), but at least we have not forgotten the creeds of the church that leads all the way back to the seminal moments of history where Jesus dies on the Cross and RISES from the dead! In case someone missed that, Paul didn't do that -- nor did he remotely claim to do so. Nor did he say "upon this rock (or even this "Brock") I will build my church; and the gates of hell shall not prevail against it."
Heresies, especially Gnostic types, are a dime a dozen. We can all feel that little pang of "I've NEVER heard about THIS before, MAYBE it is true and changes everything"! When we feel it, it is a good time to read a couple creeds and get over it -- maybe with a glass of OLD Scotch .. possibly older than the new "revelation" in some cases.
It is the siren song of the latest and greatest product, the newest "study" and "progressivism" itself, the leading snake oil of our time. It's new, but it is a very old story!
Don't be fooled -- wisdom is always old and eternity is always long.