The Quran
[26:192] This is a revelation from the Lord of the universe. [26:193] The Honest Spirit (Gabriel) came down with it. [26:194] To reveal it into your heart, that you may be one of the warners. [26:195] In a perfect Arabic tongue. [26:196] It has been prophesied in the books of previous generations. [26:197] Is it not a sufficient sign for them that it was known to the scholars among the Children of Israel?
Why does God refer to Gabriel as Honest in 26:193, are not all angels honest?
Is Gabriel an angel?
[2:98] Anyone who opposes GOD, and His angels, and His messengers, and Gabriel and Michael, should know that GOD opposes the disbelievers.
[66:4] If the two of you repent to GOD, then your hearts have listened. But if you band together against him, then GOD is his ally, and so is Gabriel and the righteous believers. Also, the angels are his helpers.
From Appendix 2:
“Surely, You Are One of the Messengers” (36:3)
(21) I was told most assertively, through the angel Gabriel, that Verse 3 of Sura 36 refers specifically to me. If we arrange the initialed suras only, starting with Sura 2, then Sura 3, then Sura 7, and so on, we find that Sura 36, Ya Seen, occupies position number 19.
The Quran Consummates All Scriptures
[2:89] When this scripture came to them from GOD, and even though it agrees with, and confirms what they have, and even though they used to prophesy its advent when they talked with the disbelievers, when their own prophecy came to pass, they disbelieved therein. GOD’s condemnation thus afflicts the disbelievers.