مَنْ قَتَلَ نَفْسًا مُعَاهَدًا لَمْ يَرَحْ رَائِحَةَ الْجَنَّةِ، وَإِنَّ رِيحَهَا يُوجَدُ مِنْ مَسِيرَةِ أَرْبَعِينَ عَامًا
Whoever kills a person protected by a treaty will never smell the fragrance of Paradise, and indeed its fragrance can be found a distance of forty years of travel. [Sahih Bukhari, Volume 9, Book 83, Number 49]