﴿ فَٱرْتَقِبْ يَوْمَ تَأْتِى ٱلسَّمَآءُ بِدُخَانٍۢ مُّبِينٍۢ ﴾

“WAIT, THEN, for the Day when the skies shall bring forth a pall of smoke which will make obvious [the approach of the Last Hour],”

(But watch thou for) their torment, O Muhammad, on (the day when the sky will produce visible smoke) filling what is between the sky and the earth