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كتاب التفسير
65  
Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh))
(1b)
"It is for Us to collect it and to give you (O Muḥammad pbuh), the ability to recite it (the Qur'ān) ." (V.75:17)
(1 م)
Sahih al-Bukhari 4928

Narrated Musa bin Abi Aisha:

That he asked Sa`id bin Jubair regarding (the statement of Allah). 'Move not your tongue concerning (the Qur'an) to make haste therewith.' He said, "Ibn `Abbas said that the Prophet (ﷺ) used to move his lips when the Divine Inspiration was being revealed to him. So the Prophet (ﷺ) was ordered not to move his tongue, which he used to do, lest some words should escape his memory. 'It is for Us to collect it' means, We will collect it in your chest;' and its recitation' means, We will make you recite it. 'But when We recite it (i.e. when it is revealed to you), follow its recital; it is for Us to explain it and make it clear,' (i.e. We will explain it through your tongue).

حَدَّثَنَا عُبَيْدُ اللَّهِ بْنُ مُوسَى، عَنْ إِسْرَائِيلَ، عَنْ مُوسَى بْنِ أَبِي عَائِشَةَ، أَنَّهُ سَأَلَ سَعِيدَ بْنَ جُبَيْرٍ عَنْ قَوْلِهِ تَعَالَى ‏{‏لاَ تُحَرِّكْ بِهِ لِسَانَكَ‏}‏ قَالَ وَقَالَ ابْنُ عَبَّاسٍ كَانَ يُحَرِّكُ شَفَتَيْهِ إِذَا أُنْزِلَ عَلَيْهِ، فَقِيلَ لَهُ ‏{‏لاَ تُحَرِّكْ بِهِ لِسَانَكَ‏}‏ ـ يَخْشَى أَنْ يَنْفَلِتَ مِنْهُ ـ ‏{‏إِنَّ عَلَيْنَا جَمْعَهُ وَقُرْآنَهُ‏}‏ أَنْ نَجْمَعَهُ فِي صَدْرِكَ، وَقُرْآنَهُ أَنْ تَقْرَأَهُ ‏{‏فَإِذَا قَرَأْنَاهُ‏}‏ يَقُولُ أُنْزِلَ عَلَيْهِ ‏{‏فَاتَّبِعْ قُرْآنَهُ * ثُمَّ إِنَّ عَلَيْنَا بَيَانَهُ‏}‏ أَنْ نُبَيِّنَهُ عَلَى لِسَانِكَ‏.‏
Reference : Sahih al-Bukhari 4928
In-book reference : Book 65, Hadith 448
USC-MSA web (English) reference : Vol. 6, Book 60, Hadith 450
  (deprecated numbering scheme)