Dalil

Al-Adab Al-Mufrad 440

Someone says calls his brother an unbeliever

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حَدَّثَنَا سَعِيدُ بْنُ دَاوُدَ قَالَ حَدَّثَنَا مَالِكٌ أَنَّ نَافِعًا حَدَّثَهُ أَنَّ عَبْدَ اللهِ بْنَ عُمَرَ

أَخْبَرَهُ أَنَّ رَسُولَ اللهِ ﷺ قَالَ إِذَا قَالَ لِلْآخَرِ كَافِرٌ فَقَدْ كَفَرَ أَحَدُهُمَا إِنْ كَانَ الَّذِي قَالَ لَهُ كَافِرًا فَقَدْ صَدَقَ وَإِنْ لَمْ يَكُنْ كَمَا قَالَ لَهُ فَقَدْ بَاءَ الَّذِي قَالَ لَهُ بِالْكُفْرِ

Translation

✧ He reported that the Messenger of Allah ﷺ said, 'When one says to another, "Unbeliever," then one of them has disbelieved: if the one to whom he said it is an unbeliever, then he has spoken the truth; but if it is not as he said, then the one who said it has brought the disbelief upon himself.'

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