Surah Al-Hujurat, ayah 11

49:11

يَٰٓأَيُّهَا ٱلَّذِينَ ءَامَنُواْ لَا يَسۡخَرۡ قَوۡمٞ مِّن قَوۡمٍ عَسَىٰٓ أَن يَكُونُواْ خَيۡرٗا مِّنۡهُمۡ وَلَا نِسَآءٞ مِّن نِّسَآءٍ عَسَىٰٓ أَن يَكُنَّ خَيۡرٗا مِّنۡهُنَّۖ وَلَا تَلۡمِزُوٓاْ أَنفُسَكُمۡ وَلَا تَنَابَزُواْ بِٱلۡأَلۡقَٰبِۖ بِئۡسَ ٱلِٱسۡمُ ٱلۡفُسُوقُ بَعۡدَ ٱلۡإِيمَٰنِۚ وَمَن لَّمۡ يَتُبۡ فَأُوْلَٰٓئِكَ هُمُ ٱلظَّٰلِمُونَ ١١

Yā'ayyuhal-ladhīna āmanū lā yaskhar qawmum min qawmin 'asā an yakūnū khayram minhum walā nisā'um min nisā'in 'asā an yakunna khayram minhunna walā talmizū anfusakum walā tanābazū bil-alqābi bi salismul-fusūqu ba'dal-īmāni wamal lam yatub fa ulā'ika humuz-zālimūn

O you who have believed, let not a people ridicule [another] people; perhaps they may be better than them; nor let women ridicule [other] women; perhaps they may be better than them. And do not insult one another and do not call each other by [offensive] nicknames. Wretched is the name [i.e., mention] of disobedience after [one's] faith. And whoever does not repent - then it is those who are the wrongdoers.