Abdullah bin Umar reported,
The Messenger of Allah ﷺ said, "The Quran is like hobbled camels. If their owner keeps watch over their tethers, he holds onto them, but if he neglects them, they wander off. The one who has memorized the Quran, if he stands and recites it by night and by day, he retains it, but if he does not recite it, he forgets it."
Azami 671
Sahihعن ابن عمر
أن رسول الله ﷺ قال: إنما مثل القرآن كمثل الإبل المعقلة، إذا عاهدها صاحبها على عقلها أمسكها، وإذا أغفلها ذهبت، إذا قام صاحب القرآن فقرأه بالليل والنهار ذكره، وإذا لم يقرأه نسيه.
Nasai narrated it in Al-Kubra (7989) from Qutayba bin Saeed, who said, "Yaqub bin Abdul-Rahman told us, from Musa bin Uqba, from Ibn Umar," who said such and such.Muslim also narrated it in the Book of the Prayer of the Traveler (789:227) with this same chain, joining it to the narration of Malik, and he mentioned the addition of Musa bin Uqba in this hadith, which is his statement, "When the companion of the Quran stands and recites it by night and by day, he remembers it, but when he does not recite it, he forgets it."