NASAI-KUBRA 7989:
from Ibn ʿUmar —
[Machine] "That the Messenger of Allah ﷺ said: 'Verily the example of the Qur'an is like that of a tied camel. If its owner takes care of it, it remains with him, and if he neglects it, it goes away. Similarly, when a person establishes a relationship with the Qur'an and recites it day and night, he remembers it, but when he does not recite it, he forgets it.'"
الكبرى للنسائي ٧٩٨٩:
عن ابن عمر —
أَنَّ رَسُولَ اللهِ ﷺ قَالَ «إِنَّمَا مَثَلُ الْقُرْآنِ كَمَثَلِ الْإِبِلِ الْمُعَقَّلَةِ إِذَا عَاهَدَهَا صَاحِبُهَا عَلَى عُقُلِهَا أَمْسَكَهَا وَإِذَا أَغْفَلَهَا ذَهَبَتْ إِذَا قَامَ صَاحِبُ الْقُرْآنِ فَقَرَأَهُ بِاللَّيْلِ وَالنَّهَارِ ذَكَرَهُ وَإِذَا لَمْ يَقْرَأْهُ نَسِيَهُ»
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