We sent not an apostle except in the language of his people. (14:4)

O mankind! We created you from a single (pair) of a male and a female, and made you into nations and tribes, that ye may know each other (not that ye may despise each other). Verily the most honoured of you in the sight of God is (he who is) the most righteous of you. (49:013)

We sent thee not, but as a Mercy for all creatures. (21:107) We did aforetime send apostles before thee: of them there are some whose story We have related to thee, and some whose story We have not related to thee. (40:78)

We sent not an apostle except (to teach) in the language of his (own) people, in order to make (things) clear to them. (14:4) Thus have We revealed it to be a judgment of authority in Arabic. (13:37) We have made it a Quran in Arabic, that ye may be able to understand (and learn wisdom). (43:3)

Verily this is a Revelation from the Lord of the Worlds: (26:192)  With it came down the spirit of Faith and Truth- (26:193)  To thy heart and mind, that thou mayest admonish. (26:194)  In the perspicuous Arabic tongue. (26:195)

We have sent it down as an Arabic Quran, in order that ye may learn wisdom. (12:2) Thus have We sent by inspiration to thee an Arabic Quran: that thou mayest warn the Mother of Cities and all around her,- (42: 7) 

Had We sent this as a Quran (in the language) other than Arabic, they would have said: "Why are not its verses explained in detail? What! (a Book) not in Arabic and (a Messenger an Arab?" (41:44) Thus have We sent this down - an arabic Quran - (20:113)

A Book, whereof the verses are explained in detail;- a Quran in Arabic, for people who understand;- (41: 3) And before this, was the Book of Moses as a guide and a mercy: And this Book confirms (it) in the Arabic tongue; to admonish the unjust, and as Glad Tidings to those who do right. (46:12)