The Description of Hell
Hell is true. It is obligatory to believe in it and that it is presently created, as is understood by the verses of the Qur’an and the authentic hadith. It is a place Allah has Prepared for the torture of the blasphemers that never ceases, and it is also prepared for some of the sinful Muslims. Its place is below the seventh earth without being connected to it.
Allah will increase the size of the blasphemer in Hell so that he would be increased in torture, to the extent that his molar would be as large as Mount Uhud, and he will dwell in Hell forever and ever; he will not die in it and he will not live.[1] They will not have food it except from the plant of dari^, and their drink will be from hot water that has reached the extremity of heat.
As for Paradise being above the seventh sky, that is confirmed in the authenticated hadith, and that is the saying of the Prophet when he said:
وفوقَه عرشُ الرحمن
[which means] “Above it (Firdaws) is the ^Arsh of Ar-Rahman.” As for Hell being below the seventh earth, Al-Hakim said in Al-Mustadrak that authentic narrations came in reference to that.
[1] i.e., comfortably.