Sahih al-Bukhari 5033
Sahih al-Bukhari · Book 66: Virtues of the Qur'an · The learning of the Qur'an by heart and the reciting of it repeatedly
Narrated Abu Musa:
حَدَّثَنَا مُحَمَّدُ بْنُ الْعَلاَءِ ، حَدَّثَنَا أَبُو أُسَامَةَ ، عَنْ بُرَيْدٍ ، عَنْ أَبِي بُرْدَةَ ، عَنْ أَبِي مُوسَى ، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ " تَعَاهَدُوا الْقُرْآنَ فَوَالَّذِي نَفْسِي بِيَدِهِ لَهُوَ أَشَدُّ تَفَصِّيًا مِنَ الإِبِلِ فِي عُقُلِهَا " .
The Prophet (ﷺ) said, "Commit yourself to the Qur'an, for by Him in whose Hand is my soul, it is surely more prone to break away than a camel in its bind.