You've definitely heard it. You've likely grown up rehearsing it to yourself or others; and you may even believe it to this day. Some versions are very similar to other traditional fairytales: soft and ethereal, with no exact definitions or explanations.
And yet some are very detailed, filled with an abundance of truth and doctrinal precision, making their fairytale nature all the more insidious - but it's there.
"Yes, God is divine. Jesus is the Son of God, born of a virgin, perfectly man and perfectly God in one person. Justification is by faith in the substitution of Christ alone. Scripture alone is the authoritative word of God, et cetera, et cetera, et cetera. "(of course, the "et cetera" would never be said explicitly - but when speaking of a fairytale, it is always implied).
The "Christian" Fairytale can be absolutely full of good Christian truth. So what makes it a fairytale, you ask? Its foundation. Ask the modern Christian why he believes Christianity to be true, and you will not ultimately hear objective reasons or rationale. That would rely too heavily on "human wisdom." Having objective reasons to believe that the Bible is true, or that God exists, or that Christ is God would "leave no room for faith." Citing any objective rationale for belief would be an attempt to "build a ladder of reason to God" which is considered the height of arrogance by modern evangelicals.
What you will hear instead is something along the lines of "it's what I believe to be true"; "it's the 'perspective' which I have chosen to start with"; "it's so full of good for humanity"; in other words: Christianity is true because we want it to be true. Christianity is our grand fairytale.
Such is the cause of the phenomenon that modern Christians refer to as "compartmentalizing your Christian life." They see it as a mere surface level piety issue; i.e. not being serious enough about carrying your "Christian" fairytale into every area of life. But that is just a symptom. The disease is the fact that Christianity really is nothing more than a fairytale to many professing believers––and deep down, they know it.
They don't allow Christianity to affect their lives and reality the way that it should because they have no category for Christianity actually being true about reality. How could they? They are morally forbidden from consciously identifying any link between Christianity and objective reality, lest they be accused of arrogantly attempting to discover God "on their own" -- whatever that means. Their only alternative (if they want to remain Christian - and that's a big if today) is to constantly try to work themselves up into emotional frenzies via pep-talks, to-do lists, self-help books, motivational speakers, and constant guilt through condemnation in order to motivate them to keep on faking what they think deep down to be a big joke.
Why this rabid insistence on avoiding objective analysis of Christianity, though? Why would Christians want to ultimately treat Christianity like a fairytale? There are many potential answers which could be explored, with a whole host of flawed philosophical assumptions - but at the bottom of it all, I think you would find a common emotion: fear. Why do Christians treat Christianity like a fairytale? Why don't they want to assess it objectively with reason? Because they are afraid that they might discover that it's not actually true. Deep down, these supposedly pious Christians have a sneaking suspicion that it's all a big ruse.
In other words, they subconsciously agree with the atheist: God isn't actually real, Christ wasn't actually God, Scripture is actually full of errors, and we just have to get along the best we can in this life. The only difference: the Christian views the "Christian" fairytale as the best way to get along in this life and the atheist doesn't. But both are at war against the Christian who wants to treat Christianity as objectively true about reality. The atheist wars against the ideas. The fairytale Christian wars against the objective Christian's defense -- leaving true and objective Christianity with no leg to stand on. Such is the state of modern Christianity. Nothing more than a fairytale. That's gotta be pretty flattering to God..
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