It is the soora 44 in the book of the Quran:


Soora 44

(In the name of God, Most Gracious, Most Merciful)

1. Ha, Miem:
[These abbreviated Arabic letters mean:]
Wisdom [or admonition, and] Repeated [stories.] [: W. R.]

2. And the enlightening scripture.

3. We [started] revealing the [Quran] on a blessed night; for surely We [now as in the past] are warning [people against worshiping the idols.]

4. During which all the admonishing am'rs [: angels] are distributed [to admonish the believers by the way of inspiration.]

[Then God be glorified said:]
5. [Such] Am'r [: angels] coming from Our [neighborhood in the ethereal heavens, the dwelling-place of angels]; We sent [angels to the prophets and apostles in the past.]

[Then God be glorified explained that sending of these angels to the prophets and messengers is part of His mercy to people, for they guide them to the way of the truth, so they will be safe of the punishment and enter Paradise.
This is concerning the Next Life; while in the life of the World, this will remove from them their loving and worshiping of statues, and remove from them the ignorance and their bad habits and acquaint them with valuable religious and Worldly knowledge; therefore, their minds will attain high level, and their souls reach the high ranks of perfection, dignity and honor; so God be glorified said:]

6. [Sending those angels is] a mercy from your Lord [O Mohammed;] He is the All-Hearing [of their prayer], the All-Knowing [of their circumstances.]

7. The Lord of the heavens and the earth and all that is between them; so if you are certain [about that, then be certain about the words of Mohammed, Our messenger].

8. There is no god [in the universe] but He [alone.]
He gives life [to the inanimate making out of it the living beings],
And [He] causes death [of the living beings: He is All-Able to do either of these];
your Lord and the Lord of your forefathers.

The rest of the soora and a further explanation is in the link: