The holy Quran says in verse 15 of Sura Al-Maedah: "O followers of the Book! indeed Our Messenger has come to you making clear to you much of what you concealed of the Book and passing over much; indeed, there has come to you light and a clear Book from Allah."[i]

The commentators of the Holy Quran have said in the interpretation of this verse: "This sentence of the Quranic verse signifies the importance and greatness of the Holy Quran and its profound impact on human guidance and education."[ii] That is because the word "Book" in this verse has been used in the indefinite (nakirah) which somehow implies greatness and dignity[iii].

Late Allamah Tabatabai has said, "The sentence "wa kitabun mubin" is a coordinating conjunction explaining the word "noor". That is to say, the word "light" in the Quran refers to the Holy Quran. Technically, "clear Book" is an explanatory conjunction. That is, "a light has come down from God which is the clear Book".[iv]

In this verse, the word "clear" defines the Quran so as to make it distinct from other heavenly or non-heavenly books because no other book provides so clear and plain guidance and instructions as the Quran does.

The fact that the Quran repeats time and again that God has sent down the Quran is to remind people of the bounty of guidance so that they may not become negligent of the realities, guidelines and injunctions. Definitely, all these sayings should be after the revelation of the Quran not before it. Because if God says that He sent down the Book before its revelation, it is a lie. Additionally, many unbelievers as well as pagans had spread the rumor that the Quran had been written by the Prophet himself, peace be upon him and his family. The Quran dispels such a satanic and false assumption by reiterating and emphasizing on the fact that it (Quran) was sent down by God.

Therefore, in this holy verse, the revelation of the Quran means that it was sent down upon the Prophet (s) so that he would declare and make it known to people. It is not explaining something which is already clear.