Allah said,

﴿فَاتَّقُواْ النَّارَ الَّتِى وَقُودُهَا النَّاسُ وَالْحِجَارَةُ أُعِدَّتْ لِلْكَـفِرِينَ﴾

(Then fear the Fire (Hell) whose fuel is men and stones, prepared for the disbelievers) (2:24).

`Fuel' is wood, or similar substances, used to start and feed a fire. Similarly, Allah said,

﴿وَأَمَّا الْقَـسِطُونَ فَكَانُواْ لِجَهَنَّمَ حَطَباً ﴾

(And as for the Qasitun (disbelievers who deviated from the right path), they shall be firewood for Hell) (72:15), and,

﴿إِنَّكُمْ وَمَا تَعْبُدُونَ مِن دُونِ اللَّهِ حَصَبُ جَهَنَّمَ أَنتُمْ لَهَا وَارِدُونَ ﴾

﴿لَوْ كَانَ هَـؤُلاءِ ءَالِهَةً مَّا وَرَدُوهَا وَكُلٌّ فِيهَا خَـلِدُونَ ﴾

(Certainly you (disbelievers) and that which you are worshipping now besides Allah, are (but) fuel for Hell! (Surely) you enter it. Had these (idols) been alihah (gods), they would not have entered there (Hell), and all of them will abide therein) (21:98-99).

The stones mentioned here are the giant, rotten, black, sulfuric stones that become the hottest when heated, may Allah save us from this evil end. It was also reported that the stones mentioned here are the idols and rivals that were worshipped instead of Allah, just as Allah said,

﴿إِنَّكُمْ وَمَا تَعْبُدُونَ مِن دُونِ اللَّهِ حَصَبُ جَهَنَّمَ﴾

(Certainly you (disbelievers) and that which you are worshipping now besides Allah,are (but) fuel for Hell!) (21:28).

Allah's statement,

﴿أُعِدَّتْ لِلْكَـفِرِينَ﴾

(prepared for the disbelievers)

It appears most obvious that it refers to the Fire that is fueled by men and stones, and it also may refer to the stones themselves. There is no contradiction between these two views, because they are dependent upon each other. `Prepared' means, it is `kept' and will surely touch those who disbelieve in Allah and His Messenger . Ibn Ishaq narrated that Muhammad said that `Ikrimah or Sa`id bin Jubayr said that Ibn `Abbas said,

﴿أُعِدَّتْ لِلْكَـفِرِينَ﴾

(prepared for the disbelievers),

"For those who embrace the disbelief that you (disbelievers) have embraced.''