Surah 85. Al-Buruj, Ayah 22

Lit., "upon a well-guarded tablet (lawh mahfuz)" - a description of the Qur'an to be found only in this one instance. Although some commentators take it in its literal sense and understand by it an actual "heavenly tablet" upon which the Qur'an is inscribed since all eternity, to many others the phrase has always had a metaphorical meaning: namely, an allusion to the imperishable quality of this divine writ. This interpretation is pointedly mentioned as justified by, e.g., Tabari, Baghawi, Razi or Ibn Kathir, all of whom agree that the phrase "upon a well-guarded tablet" relates to God's promise that the Qur'an would never be corrupted, and would remain free of all arbitrary additions, diminutions and textual changes. See in this connection also 15:9 and the corresponding note [10].

"Inscribed in a Tablet Preserved", i.e. Allah's Message is not ephemeral. It is eternal. The "Tablet" is "preserved" or guarded from corruption: xv. 9: for Allah's Message must endure for ever. That Message is the "Mother of the book": see n. 347 to iii. 7.