Sahih al-Bukhari 3166
Sahih al-Bukhari · Book 58: Jizyah and Mawaada'ah · The sin of one who kills an innocent person having a treaty with the Muslims
Narrated `Abdullah bin `Amr:
حَدَّثَنَا قَيْسُ بْنُ حَفْصٍ ، حَدَّثَنَا عَبْدُ الْوَاحِدِ ، حَدَّثَنَا الْحَسَنُ بْنُ عَمْرٍو ، حَدَّثَنَا مُجَاهِدٌ ، عَنْ عَبْدِ اللَّهِ بْنِ عَمْرٍو ـ رضى الله عنهما ـ عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ " مَنْ قَتَلَ مُعَاهَدًا لَمْ يَرَحْ رَائِحَةَ الْجَنَّةِ، وَإِنَّ رِيحَهَا تُوجَدُ مِنْ مَسِيرَةِ أَرْبَعِينَ عَامًا " .
The Prophet (ﷺ) said, "Whoever killed a person having a treaty with the Muslims, shall not smell the smell of Paradise though its smell is perceived from a distance of forty years."