I got this idea from Skeptics Annotated Quran. In the Quran Allah is described many times as merciful, & at other times as utterly merciless, detailing the tortures He will inflict on the person of unbelievers'. Allah has sealed the unbelievers' hearts from beforehand, thus it isn't exactly the unbelievers' fault that they can't believe! But try explaining that to Allah who'll roast unbelievers' in Hell!
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Here are the verses:
Verses Claiming that Allah is Merciful!Thou, only Thou, art the Relenting, the Merciful.
2:143
For Allah is Full of Pity, Merciful toward mankind.
2:160
I am the Relenting, the Merciful.
2:173,
Verses Claiming that Allah is Revengeful!:
2:7
Allah hath sealed their hearing and their hearts, and on their eyes there is a covering.
2:17
Allah taketh away their light and leaveth them in darkness, where they cannot see.
4:56
Those who disbelieve Our revelations, We shall expose them to the Fire. As often as their skins are consumed We shall exchange them for fresh skins that they may taste the torment.
4:168-9
Lo! those who disbelieve and deal wrong, Allah will never forgive them, neither will He guide them unto a road, Except the road of hell, wherein they will abide for ever. And that is ever easy for Allah.
7:50
And the dwellers of the Fire cry out unto the dwellers of the Garden: Pour on us some water or some wherewith Allah hath provided you. They say: Lo! Allah hath forbidden both to disbelievers (in His guidance).
With all these lengthy & gleeful descriptions of Allah's cruelty towards unbelievers, & the fact that Allah has sealed unbelievers' hearts from before, how can Allah make the claim that He's merciful?
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