I'm sure this has been asked before. But not since I joined. I'm mainly concerned with Biblical authority and/or inerrancy. What's the verdict so far as you can tell?
Is Christianity true because the Bible says so?
Or does the Bible say so because it describes the truth of Christianity?
You ask a good question. Many people are in this cycle of circular reasoning.
Somethings Muslims do: "I believe in hell because the Quran says so", yet, "I believe in Quran because it's amazing + rational + a miracle". Well the rational part is dependent on hell being a rational belief.
Now it's true that Mohammad (s) is sent to warn about the day of judgment and hell. But then if this is true, they have be double implications.
The day of judgment must imply God will send Messengers (to prove it). And God's sent ones will prove the day of judgment. But this means also they have to be independently proven. And we have to at least see one of the proofs to be true.
I realized that hell especially since how much of the Quran has devoted to explaining and justifying it from many angles, and repeated it, cannot be taken on blind faith. Other things like did Dul-Qarnain (a) exist, are things you cannot know outside of trust of Quran. The heart repeated warnings however, cannot be, something to blindly say, well Quran says so. Because they are at the heart of the structure of the Quran. So if it fails, the Quran fails, and it's contingent on it's truth.
As you know from another forum, I was a Deist/New Age type person who didn't believe in hell and had left Islam for 5 years.
Also, the heart of the paradigm of the Quran is to believe in the unseen nature of God's signs. This ranges from signs in our souls to signs in the horizon to the nature of God's book and is descending and ascending nature.
Since somethings are the heart and focus and basis of the structure of the Quran, you have to prove it to be rational and proven by how Quran proves it and discusses it or otherwise, you cannot accept the Quran.
However, then there is specific things, that you cannot know without knowing Quran is true. It can't prove it in philosophical matter, but rather you accept it when you know Quran is proven to be true.