Surah 2

Surah 2:4

"and who believe in what has been sent down to you, and what was sent down before you, and they are certain of the Hereafter."

2.4 – in what has been sent down to you

The Quran claims that its contents are “sent down” to the messenger. This is the Quran’s normal vocabulary of revelation (nazzala, anzala, tanzīl). This expression helpfully indicates that frequently in the Quran the “belief” in view is not a general “religious faith” but the particular belief that the messenger is a true prophet and that Allah “sends down” the messenger’s recitations.

The Quran frequently addresses personal messages to the messenger. Muslims believe that the Quran’s voice is Allah, that the messenger is Muhammad, and that the recitation “sent down” is the Quran.

2.4 – and what was sent down before you

The Quran shows an awareness of revelations prior to Islam. In this way the Quran raises the question of the relationship between the messenger’s recitation and the pre-Islamic scriptures.

- from The Quran with Christian Commentary: A Guide to Understanding the Scripture of Islam