سورة التكاثر

Imam Sadiq (peace be upon him): Hisham ibn Salim narrated from Imam Sadiq (peace be upon him) that he said concerning the words of Allah the Exalted: لَوْ تَعْلَمُونَ عِلْمَ الْیَقِینِ [If you had known with the knowledge of certainty]: "[It means] seeing with the eye."

Ibn Abbas (may Allah have mercy on him): The Messenger of Allah (peace be upon him and his family) recited Surah al-Takathur ... کَلَّا لَوْ تَعْلَمُونَ عِلْمَ الْیَقِین [Nay! if you had known with a certain knowledge]; and the Sirat will be brought and placed over the two edges of Hell, and you will most certainly come to know things.