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كتاب التفسير
65  
Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh))
(4)
The Statement of Allah "Who have made the Qur'an into parts (i.e., believed in one part and disbelieved in the other) ." (V.15:91)
(4)
Sahih al-Bukhari 4705

Narrated Ibn `Abbas:

Those who have made their Scripture into parts are the people of the Scripture who divided it into portions and believed in a part of it and disbelieved the other.

حَدَّثَنِي يَعْقُوبُ بْنُ إِبْرَاهِيمَ، حَدَّثَنَا هُشَيْمٌ، أَخْبَرَنَا أَبُو بِشْرٍ، عَنْ سَعِيدِ بْنِ جُبَيْرٍ، عَنِ ابْنِ عَبَّاسٍ، رضى الله عنهما ‏{‏الَّذِينَ جَعَلُوا الْقُرْآنَ عِضِينَ‏}‏ قَالَ هُمْ أَهْلُ الْكِتَابِ، جَزَّءُوهُ أَجْزَاءً، فَآمَنُوا بِبَعْضِهِ وَكَفَرُوا بِبَعْضِهِ‏.‏
Reference : Sahih al-Bukhari 4705
In-book reference : Book 65, Hadith 227
USC-MSA web (English) reference : Vol. 6, Book 60, Hadith 228
  (deprecated numbering scheme)