حَتَّىٰٓ إِذَا فَتَحۡنَا عَلَيۡهِم بَابٗا ذَا عَذَابٖ شَدِيدٍ إِذَا هُمۡ فِيهِ مُبۡلِسُونَ

until We open on them the gate of a severe punishment, whereupon they will be despondent in it.