Sayyiduna Ibn Mas'ud (may Allah be pleased with him) narrates that the Messenger of Allah (peace and blessings be upon him) said: "It is extremely bad for any man among you to say, 'I have forgotten such and such verse.' Rather, he should say, 'Such and such verse has been made to be forgotten by me.' Guard this Qur'an, for it escapes from people's hearts more swiftly than a camel escapes from its rope."