﴿ فَإِن لَّمْ تَفْعَلُوا۟ وَلَن تَفْعَلُوا۟ فَٱتَّقُوا۟ ٱلنَّارَ ٱلَّتِى وَقُودُهَا ٱلنَّاسُ وَٱلْحِجَارَةُ ۖ أُعِدَّتْ لِلْكَٰفِرِينَ ﴾

“And if you cannot do it-and most certainly you cannot do it-then be conscious of the fire whose fuel is human beings and stones which awaits all who deny the truth!”

(And if ye do it not-and you can never do it-) this you can never do and if you try you will never succeed (then guard yourselves against the Fire) if you are bent on not believing, for you should fear hell (whose fuel is men) the unbelievers, (and stones) of sulphur, (prepared) created, prepared and preordained (for disbelievers).