(202) بَابُ سِبَابِ الْمُسْلِمِ فُسُوقٌ
Sa'id ibn Malik reported that the Prophet, may Allah bless himand grant him peace, said, "Reviling a Muslim is deviant behaviour." (ES)
Reference (ES): Al-Adab Al-Mufrad 429 (ES)
In-book reference (ES): Book 24, Hadith 11 (ES)
English translation (ES): Book 24, Hadith 429 (ES)