Bulugh al-Maram, Book 11, Hadith 1327 (In-Book)

'Abdullah Ibn 'Umar (RAA) narrated that The Messenger of Allah said: “Whoever kills a Mu'ahid will not smell the fragrance of Paradise, even though its fragrance could be smelt at a distance of forty years.” Related by Al-Bukhari.

وَعَنْ عَبْدِ اَللَّهِ بْنِ عَمْرِو ٍ ; 1‏ عَنْ اَلنَّبِيِّ ‏- صلى الله عليه وسلم ‏-قَالَ: { "مِنْ قَتْلِ مُعَاهِداً لَمْ يَرَحْ رَائِحَةَ اَلْجَنَّةِ, وَإِنَّ رِيحَهَا لِيُوجَدَ مِنْ مَسِيرَةِ أَرْبَعِينَ عَامّاً" } أَخْرَجَهُ اَلْبُخَارِيّ ُ 2‏.‏ ‏1 ‏- تحرف في "أ" إلى "عمر".‏‏2 ‏- صحيح.‏ رواه البخاري ( 3166 )‏.‏

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also referenced under: Book 11, Hadith 1353 (English)