The Messenger of Allah ﷺ said, "The example of the one who has memorized the Quran is like the example of the owner of a hobbled camel. If he keeps watch over it, he retains it, and if he lets it loose, it goes away."
أن رسول الله ﷺ قال: إنما مثل صاحب القرآن كمثل صاحب الإبل المعقلة إن عاهد عليها أمسكها، وإن أطلقها ذهبت.
Malik narrated it in the Quran (6), from Nafi, from Abdullah bin Umar, and he related it.Bukhari narrated it in the Virtues of the Quran (5031), and Muslim in the Prayer of Travelers (789), both from the hadith of Malik, with his chain, similarly.