Muhammad bin Yahya bin Abi 'Umar محمد بن يحيى بن أبي عمر العدني · Chapters on Recitation

that the Prophet (ﷺ) said: "How horrible it is for one of them - or - one of you to say: "I have forgotten such and such Ayah,' rather he was made to forget. So be mindful of the Qur'an, for - by the One in Whose Hand is my soul - it escapes from men's hearts faster than a camel from its fetter."