The Messenger of Allah [SAW] said: "Fighting a Muslim is Kufr and defaming him is evildoing."  

أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ قِتَالُ الْمُسْلِمِ كُفْرٌ وَسِبَابُهُ فُسُوقٌ  

Yahya related to me from Malik from Ibn Shihab from Ali ibn Husayn ibn Ali from Umar ibn Uthman ibn Affan from Usama ibn Zayd that the Messenger of Allah ﷺ said, "A muslim does not inherit from a kafir."  

أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ لاَ يَرِثُ الْمُسْلِمُ الْكَافِرَ  

The Messenger of Allah [SAW] said: "Fighting a Muslim is Kufr and defaming him is evildoing." (Using translation from Nasāʾī 4104)   

أَنَّ النَّبِيَّ ﷺ قَالَ قِتَالُ الْمُسْلِمِ كُفْرٌ وَسِبَابُهُ فِسْقٌ  

[Machine] That the Prophet ﷺ ruled that a Muslim should not be killed by a non-believer.  

أَنَّ النَّبِيَّ ﷺ قَضَى أَنْ لَا يُقْتَلَ مُسْلِمٌ بِكَافِرٍ  

“A Muslim should not be killed in retaliation for the murder of a disbeliever.” (Using translation from Ibn Mājah 2659)   

قَالَ رَسُولُ اللهِ ﷺ لَا يُقْتَلُ مُسْلِمٌ بِكَافِرٍ وَلَا ذُو عَهْدٍ فِي عَهْدِهِ  

The Messenger of Allah [SAW] said: "Fighting a Muslim is Kufr and defaming him is evildoing." (Using translation from Nasāʾī 4104)  

أَنَّ رَسُولَ اللهِ ﷺ قَالَ «قَتْلُ الْمُسْلِمِ كُفْرٌ وَسِبَابُهُ فُسُوقٌ»  

"لا يُقْتَلُ مُسْلِمٌ بِكَافِرٍ".  

"لا يُؤْذَيَنَّ مُسْلِمٌ بِكَافِرٍ".  

"عَنِ الشَّعْبِىِّ قَالَ: مِنَ السُّنَّةِ لَا يُقْتَلُ مُسْلِمٌ بِكَافِرٍ".