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كتاب التوحيد
97
Oneness, Uniqueness of Allah (Tawheed)
(51)
Chapter: What is allowed as regards the interpretation of the Taurat and other Holy Books
(51)
باب مَا يَجُوزُ مِنْ تَفْسِيرِ التَّوْرَاةِ وَغَيْرِهَا مِنْ كُتُبِ اللَّهِ بِالْعَرَبِيَّةِ وَغَيْرِهَا
لِقَوْلِ اللَّهِ تَعَالَى: {فَأْتُوا بِالتَّوْرَاةِ فَاتْلُوهَا إِنْ كُنْتُمْ صَادِقِينَ}.
And Ibn 'Abbas narrated:
Abu Sufyan bin Harb told me that Heraclius called for his translator and then asked for the letter of the Prophet (ﷺ), and the former read it (thus):

"In the Name of Allah, the Most Gracious, the Merciful. (This letter is) from Muhammad bin 'Abdullah, to Heraclius. "...O people of the Scripture (Jews and Christians): Come to a word that is just between us and you that we worship none but Allah..." (V.3:64)

وَقَالَ ابْنُ عَبَّاسٍ أَخْبَرَنِي أَبُو سُفْيَانَ بْنُ حَرْبٍ، أَنَّ هِرَقْلَ، دَعَا تَرْجُمَانَهُ، ثُمَّ دَعَا بِكِتَابِ النَّبِيِّ صلى الله عليه وسلم فَقَرَأَهُ ‏"‏ بِسْمِ اللَّهِ الرَّحْمَنِ الرَّحِيمِ مِنْ مُحَمَّدٍ عَبْدِ اللَّهِ وَرَسُولِهِ إِلَى هِرَقْلَ، وَ‏{‏يَا أَهْلَ الْكِتَابِ تَعَالَوْا إِلَى كَلِمَةٍ سَوَاءٍ بَيْنَنَا وَبَيْنَكُمْ ‏}‏‏"‏ الآيَةَ‏.‏
Reference : Sahih al-Bukhari 7541
In-book reference : Book 97, Hadith 166
USC-MSA web (English) reference : Vol. 1, Book 93, Hadith 631
  (deprecated numbering scheme)