Hadith 6104 - Good Manners and Form (Al-Adab) - Sahih Al-Bukhari - صحيح البخاري - Collection of Actions, Sayings and Teachings of Prophet Muhammad (صلى الله عليه و سلم) - Kutub as-Sittah

78. Good Manners and Form (Al-Adab) - كتاب الأدب

73) Chapter: Whoever calls his brother a Kafir without any grounds

Narrated 'Abdullah bin 'Umar:

Allah's Messenger (ﷺ) said, 'If anyone says to his brother, 'O misbeliever! Then surely, one of them such."

Reference: 6104
English reference: Vol. 8, Book 73, Hadith 125
In-book reference: Book 78, Hadith 131
Grade: Sahih
Read this hadith from Darussalam Collection

73) باب مَنْ كَفَّرَ أَخَاهُ بِغَيْرِ تَأْوِيلٍ فَهْوَ كَمَا قَالَ

حَدَّثَنَا إِسْمَاعِيلُ، قَالَ حَدَّثَنِي مَالِكٌ، عَنْ عَبْدِ اللَّهِ بْنِ دِينَارٍ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ ـ رضى الله عنهما ـ أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ ‏‏‏.‏ "‏ أَيُّمَا رَجُلٍ قَالَ لأَخِيهِ يَا كَافِرُ‏.‏ فَقَدْ بَاءَ بِهَا أَحَدُهُمَا ‏"