What makes a religion become widespread? What makes it accessible and attractive to people? Why do some religions have memberships which grow into the millions, while others remain obscure and cult-like?
If one spends much time thinking about Christianity in comparison to other religions, trying to tease out its claims to exclusivity, comparing its beginnings to the beginning of other religions, one can quickly become discouraged by the similarities.
We can't simply rely on the argument that millions of people couldn't believe something that seems unlikely as a proof for our faith.
There is no good answer for why millions upon millions would believe that an angel appeared to Joseph Smith and gave him some golden plates, revealing "truths" about Jesus interacting with people in the Americas.
It seems preposterous and easily falsifiable. Where are these plates? Well, the angel took them back. What language were they written in? Reformed Egyptian, a language never seen or depicted anywhere else...except in Joseph Smith's mind. How did Joseph Smith know how to translate this unknown language? God magically revealed it to him.
It's preposterous. It's laughable. It's downright comedy gold. Yet, millions of people believe this and participate in a religion based upon the story of the golden plates.
Because Mormonism has enough basic "truth" in it for the average person to be persuaded that there might be something to it. A focus on family and service to the community, and a co-opting of most of Christianity's themes, make it accessible to people. People don't really worry about whether Joseph Smith was a big, fat liar if they are getting their basic spiritual needs met through a community of like-minded believers. Mormonism is simple enough to be appealing to people.
It's also complex enough to keep people coming back. Secret rituals, sacred spaces that one must be approved of in order to enter, and the highly organized, institutional nature of the Mormon church; all of them create a religion in which a person can spend quite a bit of time trying to obtain the next level of spirituality, the next level of approval by the religious leaders, and the feeling that they are actively going somewhere in their faith.
It "works" in some sense.
In order for something to be believed, in order for it to be perceived as True, it must be both utterly simple and very complex.
Scientology might be another candidate for the simple/complex concept. The unvarnished story of Scientology's underlying themes is as incredible and worthy of mockery as Joseph Smith's golden plates. Lord Xenu and the intergalactic battle that left behind disembodied "thetans" that invade our minds and cause us trouble, impeding our spiritual growth and success...are better suited to a comic book than to the real world. Yet, millions of people believe and participate in Scientology.
Scientology cheats in one regard that is similar to Mormonism; the holding back of "secret" knowledge until a member is deemed worthy of possessing it. It's not hard for people to believe crazy things if they are not told the nitty gritty details at the beginning of their faith. By the time they reach the proper spiritual level, they have been so encroached in the religion that it would be unthinkable to suddenly question the beliefs that have "worked" for them.
Scientology is "simple" in its belief that most of the trouble that we face as humans emanates from our mind and the destructive, negative thoughts we perpetuate. There is enough "truth" in that belief to appeal to people. Most people have the ability to recognize that they are frequently their own worst enemies. Scientology thrives on that simple "truth" and builds a complexity into it with all sorts of elaborations and secret knowledge. It keeps people coming back, hoping to obtain new levels in the religion.
The simple/complex principle pops up everywhere. Even the most uneducated person in the world understands gravity and what will happen to them if they fall off a ladder, and yet scientists spend their life's work exploring the ramifications of gravity on the macro and micro levels. The way gravity interacts with other forces is stunningly complex...but a five-year old doesn't need the stunningly complex explanation to know that the theory of gravity is "true".
The creationism/evolution debate is raging in faith communities because of the simple/complex concept. While creationism, on its face, may seem much simpler with its "God did it all in 6 days" answer, in comparison to evolution, I believe that creationism is failing because it is becoming much more complicated to believe in it. It isn't "simple" anymore. In order to explain discrepancies with scientific data, it has to posit scientific conspiracies and a God who wanted to "trick" us by making things seem older than they really are. Once a trickster God enters the picture, and the whole scientific community is viewed as a conspiracy-minded Illuminati, simplicity goes out the window.
Evolution, though complex, is also a simple enough concept that the general population can understand it and appreciate the "truth" of things changing and becoming new things....because our own lives, and bodies, are always changing. Evolution fits into concepts we already have.
Any "truth" that is really True must fit into the Simple/Complex category.
This comes into play in Christianity through our doctrine, what we believe, and how we approach finding the "answer" to something.
If we're trying to understand what Scripture says about something and our interpretation relies on an intricate, difficult to understand principle, then we need to re-think our interpretation. On the other hand, if everything gets boiled to down to "Be Nice", with no engagement of how exactly we do that in a complex, social environment, then that interpretation fails just as rapidly as the overly complex interpretation.
Often I read bloggers who are slightly snobby in their approach to Scripture, academics, and the right way to interpret a passage, sing worship songs and promote Christianity. They advocate that people should put in long, hard years of study before being allowed a public platform, or leadership, in churches or religious societies. I see their point and agree to some extent.
However, if a belief system operates at such a complex level that the novice can find no place to enter into it, no way to easily integrate it into their lives, then that belief system fails on a very substantive level. If only experts can apprehend a supposedly universal concept, then the concept must not be very universal.
If one has to learn Hebrew and Greek in order to properly understand Scripture and find the points of truth it holds, then it calls into question the idea that Scripture is meant to be understood and have an audience made up of common, average people. If one has to learn Hebrew and Greek, not to simply understand the text, but to better clarify details, fleshing out already established, simple truths, then one has found an approach that integrates the simple/complex concept quite nicely.