أَخْبَرَنَا مَحْمُودُ بْنُ غَيْلاَنَ، قَالَ حَدَّثَنَا أَبُو دَاوُدَ، عَنْ شُعْبَةَ، قَالَ أَخْبَرَنِي مَنْصُورٌ، قَالَ سَمِعْتُ رِبْعِيًّا، يُحَدِّثُ عَنْ أَبِي بَكْرَةَ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏"‏ إِذَا أَشَارَ الْمُسْلِمُ عَلَى أَخِيهِ الْمُسْلِمِ بِالسِّلاَحِ فَهُمَا عَلَى جُرُفِ جَهَنَّمَ فَإِذَا قَتَلَهُ خَرَّا جَمِيعًا فِيهَا ‏"‏ ‏.‏

It was narrated from Abu Musa Al-Ash'ari that

The Messenger of Allah [SAW] said: "If two Muslims confront each other with swords and one of them kills the other, then the killer and the slain will both be in Hell." A man 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."