Al-Hujuraat - 49:11

يَا أَيُّهَا الَّذِينَ آمَنُوا لَا يَسْخَرْ قَومٌ مِّن قَوْمٍ عَسَى أَن يَكُونُوا خَيْرًا مِّنْهُمْ وَلَا نِسَاء مِّن نِّسَاء عَسَى أَن يَكُنَّ خَيْرًا مِّنْهُنَّ وَلَا تَلْمِزُوا أَنفُسَكُمْ وَلَا تَنَابَزُوا بِالْأَلْقَابِ بِئْسَ الاِسْمُ الْفُسُوقُ بَعْدَ الْإِيمَانِ وَمَن لَّمْ يَتُبْ فَأُوْلَئِكَ هُمُ الظَّالِمُونَ
[49:11]
O you who believe! let not (one) people laugh at (another) people perchance they may be better than they, nor let women (laugh) at (other) women, perchance they may be better than they; and do not find fault with your own people nor call one another by nicknames; evil is a bad name after faith, and whoever does not turn, these it is that are the unjust.
O ye who believe! Let not some men among you laugh at others: It may be that the (latter) are better than the (former): Nor let some women laugh at others: It may be that the (latter are better than the (former): Nor defame nor be sarcastic to each other, nor call each other by (offensive) nicknames: Ill-seeming is a name connoting wickedness, (to be used of one) after he has believed: And those who do not desist are (indeed) doing wrong.
O ye who believe! Let not a folk deride a folk who may be better than they (are), not let women (deride) women who may be better than they are; neither defame one another, nor insult one another by nicknames. Bad is the name of lewdness after faith. And whoso turneth not in repentance, such are evil-doers.