(198) بَابُ السِّبَابِ
'Abdullah said, "When a man says to his companion, 'You are myenemy,' then one of them has left Islam or he is innocent of what his companionsaid.'"
Reference: Al-Adab Al-Mufrad 421
In-book reference: Book 24, Hadith 3
English translation: Book 24, Hadith 421