Sahih Muslim Book - 33, Hadith - 4894

حَدَّثَنَا مُحَمَّدُ بْنُ رَافِعٍ ، حَدَّثَنَا عَبْدُ الرَّزَّاقِ ، أَخْبَرَنَا مَعْمَرٌ ، عَنْ هَمَّامِ بْنِ مُنَبِّهٍ ، قَالَ: هَذَا مَا: حَدَّثَنَا أَبُو هُرَيْرَةَ ، عَنْ رَسُولِ اللهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ ، فَذَكَرَ أَحَادِيثَ مِنْهَا ، وَقَالَ رَسُولُ اللهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: يَضْحَكُ اللَّهُ لِرَجُلَيْنِ يَقْتُلُ أَحَدُهُمَا الآخَرَ كِلاَهُمَا يَدْخُلُ الْجَنَّةَ ، قَالُوا: كَيْفَ يَا رَسُولَ اللهِ ، ؟ قَالَ: يُقْتَلُ هَذَا فَيَلِجُ الْجَنَّةَ ، ثُمَّ يَتُوبُ اللَّهُ عَلَى الآخَرِ ، فَيَهْدِيهِ إِلَى الإِسْلاَمِ ، ثُمَّ يُجَاهِدُ فِي سَبِيلِ اللهِ ، فَيُسْتَشْهَدُ.

It was narrated that Hammam bin Munabbih said: "This is what Abu Hurairah narrated from the Messenger of Allah (s.a.w)," - and he mentioned a number of Ahadith, including the following: "The Messenger of Allah (s.a.w) said: 'Allah will laugh at two men, one of whom killed the other, both of whom will enter Paradise.' They said: 'How is that, O Messenger of Allah?' He said: 'One fought and entered Paradise, then Allah turned in forgiveness to the other, and guided him to Islam, then he fought in Jihad in the cause of Allah and was martyred."'