عَنْ أَبِي مُوسَى الْأَشْعَرِيِّ رَضِيَ اللَّهُ عَنْهُ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «تَعَاهَدُوا الْقُرْآنَ فَوَالَّذِي نَفْسِي بِيَدِهِ لَهْوَ أَشَدُّ تَفَصِّيًا مِنَ الْإِبِلِ فِي عُقُلِهَا»
Translation

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.)