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Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
ahmad:4178 – Muḥammad b. Jaʿfar > Shuʿbah > Manṣūr And Zubayd > Abū Wāʾil > ʿAbdullāh

[Machine] On the authority of the Prophet ﷺ, he said, "Reviling a believer is an act of immorality (sin), and fighting against him is an act of disbelief (kufr)." In another hadith of Zubayd, I heard Aba Wa'il say.  

أحمد:٤١٧٨ – حَدَّثَنَا مُحَمَّدُ بْنُ جَعْفَرٍ حَدَّثَنَا شُعْبَةُ عَنْ مَنْصُورٍ وَزُبَيْدٌ عَنْ أَبِي وَائِلٍ عَنْ عَبْدِ اللهِ

عَنِ النَّبِيِّ ﷺ أَنَّهُ قَالَ سِبَابُ الْمُؤْمِنِ فِسْقٌ وَقِتَالُهُ كُفْرٌ قَالَ فِي حَدِيثِ زُبَيْدٍ سَمِعْتُ أَبَا وَائِلٍ  

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Collected by Aḥmad
ahmad:3647 – Yaḥyá > Shuʿbah > Zubayd > Abū Wāʾil > ʿAbdullāh

The Prophet ﷺ said, "Abusing a Muslim is Fusuq (an evil doing) and killing him is Kufr (disbelief)." (Using translation from Bukhārī 48)  

أحمد:٣٦٤٧ – حَدَّثَنَا يَحْيَى عَنْ شُعْبَةَ حَدَّثَنِي زُبَيْدٌ عَنْ أَبِي وَائِلٍ عَنْ عَبْدِ اللهِ

عَنِ النَّبِيِّ ﷺ قَالَ سِبَابُ الْمُسْلِمِ فُسُوقٌوَقِتَالُهُ كُفْرٌ قَالَ قُلْتُ لِأَبِي وَائِلٍ أَنْتَ سَمِعْتَ مِنْ عَبْدِ اللهِ قَالَ نَعَمْ