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كتاب التفسير
65  
Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh))
(6)
The Statement of Allah the Exalted: "...And to Dāwūd (David) We gave the Zabūr (Psalms) ." (V.17:55)
(6)
Sahih al-Bukhari 4713

Narrated Abu Huraira:

The Prophet (ﷺ) said, "The recitation of Psalms (David's Qur'an) was made light and easy for David that he used to have his ridding animal be saddled while he would finish the recitation before the servant had saddled it."

حَدَّثَنِي إِسْحَاقُ بْنُ نَصْرٍ، حَدَّثَنَا عَبْدُ الرَّزَّاقِ، عَنْ مَعْمَرٍ، عَنْ هَمَّامٍ، عَنْ أَبِي هُرَيْرَةَ ـ رضى الله عنه ـ عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ ‏ "‏ خُفِّفَ عَلَى دَاوُدَ الْقِرَاءَةُ، فَكَانَ يَأْمُرُ بِدَابَّتِهِ لِتُسْرَجَ، فَكَانَ يَقْرَأُ قَبْلَ أَنْ يَفْرُغَ ‏"‏‏.‏ يَعْنِي الْقُرْآنَ‏.‏
Reference : Sahih al-Bukhari 4713
In-book reference : Book 65, Hadith 235
USC-MSA web (English) reference : Vol. 6, Book 60, Hadith 237
  (deprecated numbering scheme)