﴿ وَإِن يَرَوْا۟ كِسْفًۭا مِّنَ ٱلسَّمَآءِ سَاقِطًۭا يَقُولُوا۟ سَحَابٌۭ مَّرْكُومٌۭ ﴾

“AND YET, if they [who refuse to see the truth] were to see part of the sky falling down, they would [only] say, “[It is but] a mass of clouds!””

(And if they) the disbelievers of Mecca (were to see a fragment of the heaven falling, they would say: A heap of clouds) because of their denial.