﴿ إِذْ تَلَقَّوْنَهُۥ بِأَلْسِنَتِكُمْ وَتَقُولُونَ بِأَفْوَاهِكُم مَّا لَيْسَ لَكُم بِهِۦ عِلْمٌۭ وَتَحْسَبُونَهُۥ هَيِّنًۭا وَهُوَ عِندَ ٱللَّهِ عَظِيمٌۭ ﴾

“when you take it up with your tongues, uttering with your mouths something of which you have no knowledge, and deeming it a light matter whereas in the sight of God it is an awful thing!”

(When ye welcomed it with your tongues) when you related the slander to each other, (and uttered with your mouths that whereof ye had no knowledge) proof or clarification, (ye counted it) i.e. the slander of 'A'ishah (a trifle) an insignificant sin. (In the sight of Allah it is very great) in terms of punishment.