I spent 4 years of my life on the Neverending story threads debating that very issue. We wrote a book in that discussion. And the same can be done here. The essential problem is that amongst the divisions you'll find parts of the truth. In basic form, the groups have adopted philosophies that they adhere to - "the wisdom of men" as it were. They follow that "wisdom of men", stick a bible in the trunk for the occasional thing not answered by the philosophy and call it "christian". By this model, I could build a philosophy for whores (literally prostitutes - not metaphorically) dabble the philosophy with calls to authority from scriptures taken out of context and say I have a Christian branch for whores. How do you suppose groups calling themselves christian give assent to the idea that the unrepentant belong in the pulpit? They may belong in church post-repentance; but, in no way belong in the pulpit.
So long as what calls itself "christian" is following something else and paying lipservice to the authority of the scriptures or building philosophies on scripture taken way out of context, all you have is people playing at religianity by following two masters and pretending they're following Christ. Many of them you can't get to defend the Bible at any cost. But, attack their philosophy and they'll defend it to the death. Therein is the folly I present as error of assumption in uniting it. It is no different than taking the religions of Old rome, banding them together and calling them the "universal religion". If Tamuz is mutually exclusive of Apollo, what truth have you preserved and what unity have you accomplished. Unity in name only is not unity.
We aren't here, as christians, to unify false doctrines into a whole. We're here to shine the light of truth. That is not served by bouding up falsehoods and giving creedance to claims of christianity while people follow anything but. And if the point is to tell people they can't follow two masters, what do you propose to do with their philosophies if you unite them? Do you do away with them (one hopes) and force them to the scriptures only? Do you call it tradition and lump all the philosophers into one volume, leaving a pantheon of masters to follow? Do you "harmonize" the philosophies into one and end yourself up with two masters again?
I understand my querries likely step squarely on your toes as Rome and many of the protestant sects are immersed in philosophy. While the Bibles they hold may be compatible to some extent, the philosophies largely have not one whit of unity either with scripture or with each other as a result. Where then is the basis for unity? The flesh? The flesh is that which we are not trying to save - bringing us back to the starting point.
"By this model, I could build a philosophy for whores (literally prostitutes - not metaphorically) dabble the philosophy with calls to authority from scriptures taken out of context and say I have a Christian branch for whores."
Jesus' Church is the one for whores.
Literally.
Look in his own bloodline: Rahab the Harlot. Remember, she was the one accoutered GOOD for her deed in Jerhico...and all despite the fact she was a whore.
And then when Jesus walked, who did he observe flocked to him: the prostitutes and tax collectors, not the Pharisees.
Now, do we suppose that prostitutes were able to stop prostitution completely in those hard days even if they loved Jesus? And starve. Jesus did not hate whores. He loved them, they loved him. Love the sinner, hate the sin.
And their sin is, what? Evil behavior undertaken because of extreme poverty. More forgiveable than evil behavior undertaken by the powerful and the rich.
Who said so?
Him.
Real Christianity has always been the religion for whores.
Whatever rejects the whores who do what they do in desperation rejects Christ. HE embraced them and loved them and understood them, and was descended from one.