Al-Mutaffifin 83:34 - Linguistic Miracle

Therefore, this day, those who believed, will, at the Kuffār, laugh

You laughed at them, they laugh at you now. Notice the word Kuffār which is a hyperbole form of the word Kāfir. We have covered its meaning in surah ʿAbasa. Why transition from Fujjār to Kuffār all of a sudden? Fujjār denoted their impulsiveness into sins. How they tried to compete and get ahead of each other in doing wrong. Kuffār intensifies the scope and magnitude of their actions. They did not just rush into any sins, but into the worst kind of sins and disobedience.

The words “at the kuffār” are advanced and hence, a better rendition of this verse is, “Therefore this day, those who believed will laugh at the kuffār, not the kuffār at those who believed.”⁸⁵ This would then be emphasizing a reversal of states. In the hereafter, the believer will laugh at the disbeliever now because of their way of life - of being engulfed by the fire and being constantly tormented. The believers would laugh at them because they knew that the disbelievers were upon nothing, and because they sold the permanent bliss for temporary pleasure; and because they have succeeded in attaining everlasting bliss, not the fleeting pleasure of the world. By holding on and by being patient for a short amount of time, they gained permanent comfort. So they were seated on couches, and looked at how the disbelievers were being punished inside Hell, and how they would be screaming inside it, and calling for death and destruction upon themselves and cursing those who led them to this fate.⁸⁶

⁸⁵ al-Ālūsī, Rūḥ al-Maʿānī, vol. 28, p. 392
⁸⁶ al-Rāzī, Mafātīḥ al-Ghayb, vol. 31, p. 103