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كتاب الجهاد والسير
56  
Fighting for the Cause of Allah (Jihaad)
(101)
Chapter: (What is said regarding the invitation of the Jews and Christians (to Islam), and for what Muslims should declare war against them and what the Prophet ﷺ wrote to Khusrau and Caesar
(101)
باب دَعْوَةِ الْيَهُودِيِّ وَالنَّصْرَانِيِّ، وَعَلَى مَا يُقَاتَلُونَ عَلَيْهِ وَمَا كَتَبَ النَّبِيُّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ إِلَى كِسْرَى وَقَيْصَرَ
Sahih al-Bukhari 2939

Narrated `Abdullah bin `Abbas:

Allah's Messenger (ﷺ) sent his letter to Khusrau and ordered his messenger to hand it over to the Governor of Bahrain who was to hand it over to Khusrau. So, when Khusrau read the letter he tore it. Sa`id bin Al- Musaiyab said, "The Prophet (ﷺ) then invoked Allah to disperse them with full dispersion, (destroy them (i.e. Khusrau and his followers) severely)".

حَدَّثَنَا عَبْدُ اللَّهِ بْنُ يُوسُفَ، حَدَّثَنَا اللَّيْثُ، قَالَ حَدَّثَنِي عُقَيْلٌ، عَنِ ابْنِ شِهَابٍ، قَالَ أَخْبَرَنِي عُبَيْدُ اللَّهِ بْنُ عَبْدِ اللَّهِ بْنِ عُتْبَةَ، أَنَّ عَبْدَ اللَّهِ بْنَ عَبَّاسٍ، أَخْبَرَهُ أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم بَعَثَ بِكِتَابِهِ إِلَى كِسْرَى، فَأَمَرَهُ أَنْ يَدْفَعَهُ إِلَى عَظِيمِ الْبَحْرَيْنِ، يَدْفَعُهُ عَظِيمُ الْبَحْرَيْنِ إِلَى كِسْرَى، فَلَمَّا قَرَأَهُ كِسْرَى خَرَّقَهُ، فَحَسِبْتُ أَنَّ سَعِيدَ بْنَ الْمُسَيَّبِ قَالَ فَدَعَا عَلَيْهِمُ النَّبِيُّ صلى الله عليه وسلم أَنْ يُمَزَّقُوا كُلَّ مُمَزَّقٍ‏.‏
Reference : Sahih al-Bukhari 2939
In-book reference : Book 56, Hadith 152
USC-MSA web (English) reference : Vol. 4, Book 52, Hadith 190
  (deprecated numbering scheme)