On the authority of ʿAbd Allāh (ibn Masʿūd), he said: "Reviling a Muslim is wickedness (fusūq), and fighting him is unbelief (kufr)." (1)

4108 – Maḥmūd ibn Ghaylān informed us, saying: Wahb ibn Jarīr narrated to us, saying: My father narrated to us, saying: I heard ʿAbd al-Malik ibn ʿUmayr narrating (2), on the authority of ʿAbd al-Raḥmān ibn ʿAbd Allāh, on the authority of his father, that the Messenger of Allāh ﷺ said: "Reviling a Muslim is wickedness, and fighting him is unbelief." (3)

4108 / m 1 – ʿAmr ibn ʿAlī informed us: Ibn Abī ʿAdīy narrated to us, on the authority of Shuʿbah, on the authority of Zubayd, who said: I said to Abū Wāʾil: "Did you hear ʿAbd Allāh say, on the authority of the Prophet ﷺ: 'Fighting a Muslim is unbelief, and reviling him is wickedness?' He said: Yes." (4) (5)

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(1) Its chain of transmission is authentic (ṣaḥīḥ). Abū al-Zaʿrāʾ is ʿAmr ibn ʿAmr – or ibn ʿĀmir – ibn Mālik ibn Naḍlah al-Jushamī. It is found in "Al-Sunan al-Kubrā" under number (3557). It has preceded in the two earlier narrations.

(2) In a copy in the margin of (K): narrating (yuḥaddith).

(3) A sound ḥadīth (ṣaḥīḥ). This chain consists of trustworthy narrators, except that ʿAbd al-Raḥmān ibn ʿAbd Allāh heard only a little from his father ʿAbd Allāh – who is Ibn Masʿūd. Wahb ibn Jarīr: he is Ibn Ḥāzim al-Azdī. It is found in "Al-Sunan al-Kubrā" under number (3558). Aḥmad (3957) and (4394), and al-Tirmidhī (2634) also transmitted it via multiple paths from ʿAbd al-Malik ibn ʿUmayr, with this chain. Al-Tirmidhī said: A ḥasan ṣaḥīḥ ḥadīth. It will follow in the four subsequent narrations via the path of Abū Wāʾil, Shaqīq ibn Salamah, from Ibn Masʿūd, raised to the Prophet (marfūʿan). Its chains are authentic.

(4) This ḥadīth and the one after it are from (M), (R), and (Q).

(5) Its chain of transmission is authentic. Ibn Abī ʿAdīy: he is Muḥammad ibn Ibrāhīm, and Zubayd: he is Ibn al-Ḥārith al-Yāmī, and Abū Wāʾil: he is Shaqīq ibn Salamah. It is found in "Al-Sunan al-Kubrā" under number (3959). Aḥmad (3647), al-Bukhārī (48), and Muslim (64): (116) also transmitted it via multiple paths from Shuʿbah, with this chain. =