Hadith 1890 a - The Book on Government - Sahih Muslim - صحيح مسلم - Collection of Actions, Sayings and Teachings of Prophet Muhammad (صلى الله عليه و سلم) - Kutub as-Sittah

33. The Book on Government - كتاب الإمارة

35) Chapter: Two Men, one of whom kills the other, and both will enter Paradise

It has been narrated on the authority of Abu Huraira that the Messenger of Allah (ﷺ) said:

God laughs at the two men both of whom will enter Paradise (though) one of them kills the other. They said: Messenger of Allah, how is it? He said: One of them fights in the way of Allah, the Almighty and Exalted. and dies a martyr. Then God turns in mercy to the murderer who embraces Islam, fights in the way of Allah, the Almighty and Exalted, and dies a martyr.

Reference: 1890 a
English reference: Book 20, Hadith 4658
In-book reference: Book 33, Hadith 188
Grade: Sahih
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35) باب بَيَانِ الرَّجُلَيْنِ يَقْتُلُ أَحَدُهُمَا الآخَرَ يَدْخُلاَنِ الْجَنَّةَ ‏‏

حَدَّثَنَا مُحَمَّدُ بْنُ أَبِي عُمَرَ الْمَكِّيُّ، حَدَّثَنَا سُفْيَانُ، عَنْ أَبِي الزِّنَادِ، عَنِ الأَعْرَجِ، عَنْ أَبِي هُرَيْرَةَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ ‏"‏ يَضْحَكُ اللَّهُ إِلَى رَجُلَيْنِ يَقْتُلُ أَحَدُهُمَا الآخَرَ كِلاَهُمَا يَدْخُلُ الْجَنَّةَ ‏"‏ ‏.‏ فَقَالُوا كَيْفَ يَا رَسُولَ اللَّهِ قَالَ ‏"‏ يُقَاتِلُ هَذَا فِي سَبِيلِ اللَّهِ عَزَّ وَجَلَّ فَيُسْتَشْهَدُ ثُمَّ يَتُوبُ اللَّهُ عَلَى الْقَاتِلِ فَيُسْلِمُ فَيُقَاتِلُ فِي سَبِيلِ اللَّهِ عَزَّ وَجَلَّ فَيُسْتَشْهَدُ ‏"‏ ‏.‏