Sunan an-Nasa'i 4118
سنن النسائي#4118Sahihأَخْبَرَنِي مُحَمَّدُ بْنُ إِسْمَاعِيلَ بْنِ إِبْرَاهِيمَ، عَنْ يَزِيدَ، عَنْ سُلَيْمَانَ التَّيْمِيِّ، عَنِ الْحَسَنِ، عَنْ أَبِي مُوسَى، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ " إِذَا تَوَاجَهَ الْمُسْلِمَانِ بِسَيْفَيْهِمَا فَقَتَلَ أَحَدُهُمَا صَاحِبَهُ فَهُمَا فِي النَّارِ " . قِيلَ يَا رَسُولَ اللَّهِ هَذَا الْقَاتِلُ فَمَا بَالُ الْمَقْتُولِ قَالَ " أَرَادَ قَتْلَ صَاحِبِهِ " .
It was narrated from Abu Musa that:The Prophet [SAW] said: "If two Muslims confront each other with swords, and one kills the other, they will both be in Hell." It was said: "O Messenger of Allah, (we understand about) the killer, but what about the one who is killed?" He said: "He wanted to kill his companion
Scholarly Authentication
The label above is the grade most of these scholars gave — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. Each scholar's own wording:
In-book reference: 37:153