Sa'd bin Abi Waqas told us that: The Messenger of Allah [SAW] said: Fighting a Muslim is Kufr and defaming him is evildoing.
It was narrated that 'Abdullah said: Defaming a Muslim is evildoing and fighting him is Kufr. (Sahih Mawquf)
It was narrated from Shu'bah, from Abu Ishaq who said: I heard Abu Al-Ahwas (narrate) that 'Abdullah said: 'Defaming a Muslim is evildoing and fighting him is Kufr.' So Aban said to him: O Abu Ishaq! You heard it only from Abu Al-Ahwas? He said: Rather, I heard it from Al-Aswad and Hubairah.
It was narrated that 'Abdullah said: Defaming a Muslim is evildoing and fighting him is Kufr. (Sahih Mawquf)
It was narrated from 'Abdur-Rahman bin 'Abdullah, from his father, that: The Messenger of Allah [SAW] said: Defaming a Muslim is evildoing and fighting him is Kufr.
It was narrated from Shu'bah who said: I said to Hammad: 'I heard Mansur, and Sulaiman, and Zubaid narrating from Abu Wa'il, from 'Abdullah, that the Messenger of Allah [SAW] said: Defaming a Muslim is evildoing and fighting him is Kufr. - Who are you worried about? Are you worried about Mansur? Are you worried about Zubaid? Are you worried about Sulaiman?' He said: 'No, but I am worried about Abu Wa'il.'
It was narrated from Sufyan bin Zubaid, from Abu Wa'il, from 'Abdullah: The Messenger of Allah [SAW] said: 'Defaming a Muslim is evildoing and fighting him is Kufr.' I said to Abu Wa'il: Did you hear it from 'Abdullah? He said: Yes.
It was narrated that 'Abdullah said: The Messenger of Allah [SAW] said: 'Defaming a Muslim is evildoing and fighting him is Kufr.'
It was narrated that Abu Wa'il said: 'Abdullah said: 'Defaming a Muslim is evildoing and fighting him is Kufr.'
It was narrated that 'Abdullah said: Fighting a believer is Kufr and defaming him is evildoing.