Al-Mursalaat - 77:14

وَمَا أَدْرَاكَ مَا يَوْمُ الْفَصْلِ
[77:14]
And what will make you comprehend what the day of decision is?
And what will explain to thee what is the Day of Sorting out?
And what will convey unto thee what the Day of Decision is! -