يَـٰٓأَيُّهَا ٱلَّذِينَ ءَامَنُوا۟ لَا يَسْخَرْ قَوْمٌ مِّن قَوْمٍ عَسَىٰٓ أَن يَكُونُوا۟ خَيْرًا مِّنْهُمْ وَلَا نِسَآءٌ مِّن نِّسَآءٍ عَسَىٰٓ أَن يَكُنَّ خَيْرًا مِّنْهُنَّ ۖ وَلَا تَلْمِزُوٓا۟ أَنفُسَكُمْ وَلَا تَنَابَزُوا۟ بِٱلْأَلْقَـٰبِ ۖ بِئْسَ ٱلِٱسْمُ ٱلْفُسُوقُ بَعْدَ ٱلْإِيمَـٰنِ ۚ وَمَن لَّمْ يَتُبْ فَأُو۟لَـٰٓئِكَ هُمُ ٱلظَّـٰلِمُونَ
yāayyuhā alladhīna āmanū lā yaskhar qawmun min qawmin ʿasā an yakūnū khayran min'hum walā nisāon min nisāin ʿasā an yakunna khayran min'hunna walā talmizū anfusakum walā tanābazū bil-alqābi bi'sa l-s'mu l-fusūqu baʿda l-īmāni waman lam yatub fa-ulāika humu l-ẓālimūna
Believers, no one group of men should jeer at another, who may after all be better than them; no one group of women should jeer at another, who may after all be better than them; do not speak ill of one another; do not use offensive nicknames for one another. How bad it is to be called a mischief-maker after accepting faith! Those who do not repent of this behaviour are evildoers.
O you who believe! Let not a group scoff at another group, it may be that the latter are better than the former. Nor let (some) women scoff at other women, it may be that the latter are better than the former. Nor defame one another, nor insult one another by nicknames. How bad is it to insult one’s brother after having Faith [i.e. to call your Muslim brother (a faithful believer) as: "O sinner", or "O wicked"]. And whosoever does not repent, then such are indeed Zâlimûn (wrong-doers, etc.).