حَدَّثَنِي مَالِكٌ، عَنْ عَبْدِ اللَّهِ بْنِ دِينَارٍ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " مَنْ قَالَ لأَخِيهِ يَا كَافِرُ . فَقَدْ بَاءَ بِهَا أَحَدُهُمَا " .
Malik related to me from Abdullah ibn Dinar from Abdullah ibnUmar that the Messenger of Allah, may Allah bless him and grant himpeace, said, "If a man says to his muslim brother, 'O kafir!' it istrue about one of them." Translation Not Available
Book Ref: Muwatta Imam Malik Book 56 Hadith 1814
Web Ref: Muwatta Imam Malik Book 56 Hadith 1