فَاليَومَ الَّذينَ آمَنوا مِنَ الكُفّارِ يَضحَكونَ
عَلَى الأَرائِكِ يَنظُرونَ
So today the faithful will laugh at the faithless,
observing from couches.
EXPOSITION
Today (al-yawm) refers to the Day of Judgement. This verse shows that justice will one day prevail and the faithful will find what they were promised. On the other hand, the faithless will find only the consequences of their actions, which is contrary to what they were laughing at.
The laughing of the believers is not a revenge resulting from a poor psychological complex, but rather it results from a deep realisation of the reality of things on the Day of Judgement; they inadvertently laughed at the simple attitude of the faithless and how they chose, with no sound reasoning, temporal temptations over the everlasting bliss they are now enjoying.
[1] Mizan, 20/239.
[2] Fadlallah, 24/142.