Mishkat al-Masabih 8 The Excellent Qualities of the Qur’an كتاب فضائل القرآن 79

وَعَنِ ابْنِ عُمَرَ أَنَّ النَّبِيَّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ: «إِنَّمَا مَثَلُ صَاحِبِ الْقُرْآنِ كَمَثَلِ صَاحِبِ الْإِبِلِ الْمُعَقَّلَةِ إِنْ عَاهَدَ عَلَيْهَا أَمْسَكَهَا وَإِنْ أَطْلَقَهَا ذَهَبَتْ»

Ibn ‘Umar reported the Prophet as saying, “He who studies the Qur’ān is like the owner of tethered camels. If he pays attention to them he keeps hold of them, but if he lets them loose they go away.” (Bukhārī and Muslim.)