The fire of hell will burn the people of hell to ashes but the point is that it is mentioned in the Quran that instead of water they will be served with puss mixed water? How come ashes need water?
Answer
The details of the hereafter have been couched in a vocabulary which the Quran describes as metaphorical (mutashabihaat). If you haven’t seen a world and you need to be introduced to it, that’s the only way to go about it. Therefore, what the people of hell would go through can only be described as fire which is the closest equivalent of it in this world. But that fire won’t burn humans to ashes, as has been clarified by the Quran.
The advantage of such a language is that you get some idea of what the other world would be like. But since the description is not literal, you don’t ask questions which you would if the description was literal.
Verse 3:7 describes the understanding I have mentioned above.
“It is He who has sent down to you, [O Muhammad], the Book; in it are verses [that are] literal – they are the foundation of the Book – and others metaphorical. As for those in whose hearts is deviation [from truth], they will follow that of it which is metaphorical, seeking mischief and seeking literal meaning of them. And no one knows its [true] meaning except Allah . But those firm in knowledge say, ‘We believe in it. All [of it] is from our Lord.’ And no one will be reminded except those of understanding”.