When I left Islam for five years, my mind was twisted in a way to find faults in Quran. But emotionally the reason I was motivated to leave Islam and find faults was the idea of hell for disbelievers (I knew the concept of mustafeen and it was not that being the problem).
How you emotional phrase a moral question like for example, why suffering exists in the world, will make you disbelieve very easily. This is why it's important for me to pay attention to the proofs and insights in Quran proving hell and particular to disbelievers and the different levels of it because without that proof and eloquently emphasizing on it, I would not be able to stay in Islam.
Here is a poem I wrote way back:
Say Islam was true
And I was a Jew
Would God torture me
For what I did not see?
In the name of justice
Pain as the flames burn
Days turn into weeks
Weeks into years
All for disbelief
I will have no relief
Billions of years pass by
Justice is still not served
All good is rejected
My good actions are ineffective
And I would not burn if my mind was reflective?
This is the creed that I use to follow
But now I realize such a creed is shallow
Whomever desires other than the true religion
Let him burn in the fire?!
As oppose to loving him, having compassion for him
Appreciating his good,
Honoring his struggles,
Being his friend,
No! No! That is not the way!
For God is enemy of those whom disbelieve!
Friend and Protector of those whom believe!
All are reduced to the lowest of the low!
Except - of course - for those all special and great believers!
Everyone but them, to hell they go!
All astray souls - be prepared for increasing burning!
For none but the guided will have peace!
Is that the remembrance that is suppose to bring ease?
Peace you say?
Bowing Five times a day!
To a Lord whom will watch humans burn in agony?
Having the believers laugh at them for the sake of an irony?
A Lord whom tortures everyone but the righteous guided?
A Lord whom loves not the disbelievers!
Hates them with a strong hatred!
And all this teachings is suppose to be sacred?
Most Merciful, Most Compassionate is he called by all!
But threatens all to hell, except those whom respond to the call?
If you have to be righteous to enter heaven.
What mercy was ever spread in creation?
Or is God accepting regret from a righteous person
Truly a show of ultra mercy, forgiveness, and compassion?
As if it's not justice to accept his regret and reformation!
At the end, O Lord of Islam!
If you are to burn me for this heresy
Then you truly were not a Lord of Mercy.
Not Worthy of Worship, not worth anyone's time.
Comment: The idea of hell being denied by the wicked people is all over Quran. At the end, the battle between truth and falsehood in my view, will be a battle between soothsayers type religion and the Prophets and sent ones religion, and there will not be different versions of the latter, because Mahdi and Jesus will bring miracles. It's just at this point, some will accuse them of being sorcerers and gained their power through skill and knowledge rather then being given that power from God which is disbelief in God's Lordship.