(202) بَابُ سِبَابِ الْمُسْلِمِ فُسُوقٌ
'Abdullah reported that the Prophet, may Allah bless him and granthim peace, said, "Reviling a Muslim is deviant behaviour and killing himis disbelief." (RU)
Reference (RU): Al-Adab Al-Mufrad 431 (RU)
In-book reference (RU): Book 24, Hadith 13 (RU)
English translation (RU): Book 24, Hadith 431 (RU)