Hadith 790 b - The Book of Prayer - Travellers - Sahih Muslim - صحيح مسلم - Collection of Actions, Sayings and Teachings of Prophet Muhammad (صلى الله عليه و سلم) - Kutub as-Sittah

6. The Book of Prayer - Travellers - كتاب صلاة المسافرين وقصرها

33) Chapter: Concerning The Careful Remembering Of The Qur'an

'Abdullah is reported to have said:

Keep refreshing your knowledge of the sacred books (or always renew your knowledge of these sacred books) and sometimes he would mention the Qur'an for it is more apt to escape from men's minds than animals which are hobbled, and the Messenger of Allah (ﷺ) said: None of you should say: I forgot such and such a verse, but he has been made to forget.

Reference: 790 b
English reference: Book 4, Hadith 1725
In-book reference: Book 6, Hadith 270
Grade: Sahih
Read this hadith from Darussalam Collection

33) باب الأَمْرِ بِتَعَهُّدِ الْقُرْآنِ وَكَرَاهَةِ قَوْلِ نَسِيتُ آيَةَ كَذَا. وَجَوَازِ قَوْلِ أُنْسِيتُهَا

حَدَّثَنَا ابْنُ نُمَيْرٍ، حَدَّثَنَا أَبِي وَأَبُو مُعَاوِيَةَ ح وَحَدَّثَنَا يَحْيَى بْنُ يَحْيَى، - وَاللَّفْظُ لَهُ - قَالَ أَخْبَرَنَا أَبُو مُعَاوِيَةَ، عَنِ الأَعْمَشِ، عَنْ شَقِيقٍ، قَالَ قَالَ عَبْدُ اللَّهِ تَعَاهَدُوا هَذِهِ الْمَصَاحِفَ - وَرُبَّمَا قَالَ الْقُرْآنَ - فَلَهُوَ أَشَدُّ تَفَصِّيًا مِنْ صُدُورِ الرِّجَالِ مِنَ النَّعَمِ مِنْ عُقُلِهِ ‏.‏ قَالَ وَقَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏‏ ‏.‏ "‏ لاَ يَقُلْ أَحَدُكُمْ نَسِيتُ آيَةَ كَيْتَ وَكَيْتَ بَلْ هُوَ نُسِّيَ ‏"