Hadith 111
قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ : " يَضْحَكُ اللَّهُ لِرَجُلَيْنِ يَقْتُلُ أَحَدُهُمَا الآخَرَ، كِلاهُمَا يَدْخُلُ الْجَنَّةَ "، قَالُوا : وَكَيْفَ يَا رَسُولَ اللَّهِ ؟ قَالَ : " يُقْتَلُ هَذَا فَيَلِجُ الْجَنَّةَ ثُمَّ يَتُوبُ اللَّهُ عَلَى الآخَرِ فَيَهْدِيهِ إِلَى الإِسْلامِ، ثُمَّ يُجَاهِدُ فِي سَبِيلِ اللَّهِ فَيُسْتَشْهَدُ "
And the Messenger of Allah, peace and blessings be upon him, said: "Allah Almighty smiles at two men, one of whom will be the killer of the other, (yet) both will enter Paradise." Upon this, the companions, may Allah be pleased with them, asked: O Messenger of Allah! How is that? The Messenger of Allah, peace and blessings be upon him, said: "(It is) that the one who fought in the way of Allah was martyred and entered Paradise. Then Allah granted the other, that is, the killer, the ability to repent and guided him to accept Islam. Then he also fought in the way of Allah and was martyred."