In another canonical recitation the wording is “and His Book.” In this connection the Exalted says:

“Say, ‘I have believed in whatever Book Allah has sent down, and I have been commanded to deal justly between you.’” (Qur’an 42:15)

He, the Most High, also says:

“Alif–Lām–Mīm.
That is the Book in which there is no doubt— a guidance for the God-fearing;
those who believe in the unseen, establish the prayer, and spend out of what We have provided for them;
and those who believe in what has been sent down to you and what was sent down before you, and who are certain of the Hereafter.
Such people are upon guidance from their Lord, and it is they who will prosper.” (Qur’an 2:1–5)

Thus He states that this Book sent down to him is a guidance for the people of piety: those who believe in the unseen, establish the prayer, pay the zakah, believe in what has been revealed to him and what was revealed before him, and are certain of the Hereafter. He then informs us that these are the successful, thereby confining success exclusively to them—no one will succeed except whoever belongs to this company.

His further statement, “and those who believe in what has been sent down to you and what was sent down before you” (Qur’an 2:4), is merely an additional description of the same people; it does not introduce a separate class. A conjunction can be used to differentiate attributes even when the subject is one and the same, and that is the correct sense here, though it has been said that the second group refers to the believers from among the People of the Book.