(Muhammad Assad)
21:39 If they but knew - they who are bent on denying the truth - [that there will come] a time when they will not be able to ward off the fire from their faces, nor from their backs, and will not find any succour!21:39
(Yousaf Ali)
21:39 If only the Unbelievers knew (the time) when they will not be able to ward off the fire from their faces, nor yet from their backs, and (when) no help can reach them!21:39