What is belief in the books?
One of the principles of belief is belief in the heavenly books. Even if man knows the existence and oneness of Allah through his mind, he cannot know what His orders and prohibitions are, how to worship Him, in short, what He will be pleased with and what He will not. Therefore, Allah sent the heavenly books.
These books are called the divine books, which mean Allah's books. They are also called holy books.
The religion of Islam orders us to believe in all of the divine books sent down by Allah. Every Muslim has to believe in both the Quran and the heavenly books informed by the Quran. Belief in the books has an important place in Islam's principles of belief.
The essence of this principle of belief is to believe that Allah sent down books to some prophets and that they are all true and real.
We do not know the exact number of the heavenly books.
According to a narration reported by Abu Idris al-Khawlani from Abu Dharr, the Prophet said Allah sent down 10 pages to Hz. Adam, 50 pages to Hz. Shet, 30 pages to Hz. Idris (Eunuch) and 10 pages to Hz. Ibrahim (Abraham). It is stated in the Quran that some pages were sent down to Hz. Ibrahim and to Hz. Musa (Moses) before the Torah was sent down. (an-Najm, 53/37-54; al-A'la, 87/19) It is also stated in the Quran that the Torah was sent down to Hz. Musa (al-Isra, 17/2; al-Maida, 5/44), the Psalms to Hz. Dawud (David) (an-Nisa, 4/163) and the Gospel to Hz. Isa (Jesus) (al-Maida, 5/46, 110).
The Quran was sent down to Hz. Muhammad (pbuh), the Seal of the Prophets.