Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
tabarani:14209ʿAlī b. ʿAbd al-ʿAzīz > Muʿallá b. Asad al-ʿAmmī > ʿAbd al-Wāḥid b. Ziyād > al-Aʿmash > Abū Khālid al-Wālibī > ʿAmr b. al-Nuʿmān b. Muqarrin

[Machine] "The Prophet ﷺ ended up in a gathering of the Ansar and there was a man among them who was known for his foul language. The Prophet ﷺ said, 'Abusing a Muslim is wickedness and fighting against them is disbelief.'"  

الطبراني:١٤٢٠٩حَدَّثَنَا عَلِيُّ بْنُ عَبْدِ الْعَزِيزِ ثَنَا مُعَلَّى بْنُ أَسَدٍ الْعَمِّيُّ ثَنَا عَبْدُ الْوَاحِدِ بْنُ زِيَادٍ عَنِ الْأَعْمَشِ عَنْ أَبِي خَالِدٍ الْوَالِبِيِّ عَنْ عَمْرِو بْنِ النُّعْمَانِ بْنِ مُقَرِّنٍ قَالَ

انْتَهَى النَّبِيُّ ﷺ إِلَى مَجْلِسٍ مِنْ مَجَالِسِ الْأَنْصَارِ وَرَجُلٌ فِيهِمْ قَدْ كَانَ يُعْرَفُ بِالْبَذَّاءِ فَقَالَ النَّبِيُّ ﷺ «سِبَابُ الْمُسْلِمِ فُسُوقُ وَقِتَالُهُ كُفْرٌ»