Is the hadith: "He who learns the Qur'an while young, Allah will mingle it with his flesh and blood," soundly attributed to the Prophet, peace and blessings be upon him, or is it from the Isra'iliyyat (Judeo-Christian traditions) through the route of Sa'id ibn Abi Hilal from al-Maqburi from Bashir ibn al-Muharrar? Can information be provided regarding its chains of transmission and the rulings of the hadith imams concerning it?

The hadith narrated from Abu Hurayrah with the wording: "Whoever learns the Qur’an in his youth, the Qur’an mixes with his flesh and blood. And whoever learns it in his old age, it escapes from him but he does not abandon it, for him is a double reward," has a sound chain of narration (saheeh isnad). There are other versions with the same wording, some of which are hasan (good) and some are da'eef (weak) or mawdu' (fabricated). As for the other wording that is not authentically reported from Abu Hurayrah, its chain of narration is flawed. A similar narration has been reported with a hasan isnad, but without mentioning learning the Qur'an in youth and old age. Similar narrations have also been reported from the Isra'iliyyat (Judeo-Christian traditions) from Ka'b al-Ahbar and Bishr ibn al-Harith, but these are not prophetic hadiths.