A man came to 'Abdullah (رضي الله عنه) and said: I have left a man in the mosque who was interpreting the Qur'an according to his own opinion. He interpreted this verse, “the Day when the sky will bring forth a visible smoke" by saying: On the Day of Resurrection a smoke will overwhelm the people which they will inhale and they will get something like a cold from it. 'Abdullah said: Whoever knows something, let him speak of it, and whoever does not know, let him say: Allah knows best. It is a part of a man's understanding of religion to say regarding that of which he has no knowledge of it, Allah knows best. This (verse) was (revealed) because when Quraish displayed a stubborn attitude towards the Prophet (ﷺ), he prayed against them and prayed for a famine like the famine of Yoosuf, and they were so afflicted by severe drought and famine that they even ate bones and a man would look at the sky and see something like smoke between him and it, because of hunger. Then a man came to the Messenger of Allah (ﷺ) and said: O Messenger of Allah, pray to Allah for rain for Mudar, for they are dying. So he prayed to Allah for them, and Allah, may He be glorified and exalted, revealed the words: “Verily. We shall remove the torment for a while.” (ad-Dukhan 44:15). But when it rained a second time, they reverted to their former ways. Then Allah, may He be glorified and exalted, revealed the words: “On the Day when We shall seize you with the greatest seizure (punishment). Verily, We will exact retribution" (ad-Dukhan 44:16) This refers to the day of Badr.