حَدَّثَنَا سُلَيْمَانُ بْنُ حَرْبٍ، قَالَ: حَدَّثَنَا شُعْبَةُ، عَنْ زُبَيْدٍ قَالَ: سَمِعْتُ أَبَا وَائِلٍ، عَنْ عَبْدِ اللهِ، عَنِ النَّبِيِّ صلى الله عليه وسلم: سِبَابُ الْمُسْلِمِ فُسُوقٌ، وَقِتَالُهُ كُفْرٌ.
'Abdullah reported that the Prophet, may Allah bless him and grant him peace, said, "Reviling a Muslim is deviant behaviour and killing him is disbelief."
Source: Al-Adab Al-Mufrad — repository translation · Imam Muhammad ibn Ismail al-Bukhari — authenticity/grade metadata requires independent source review · Sunnah.comAudio not available for the selected reciter.
Source: Al-Adab Al-Mufrad — repository arabic · Imam Muhammad ibn Ismail al-Bukhari · Sunnah.com