We have sent it down as an Arabic Qur'an, in order that ye may learn wisdom. (12:2)

Thus have We revealed it to be a judgment of authority in Arabic. Wert thou to follow their (vain) desires after the knowledge which hath reached thee, then wouldst thou find neither protector nor defender against God. (13:37)

We know indeed that they say, "It is a man that teaches him." The tongue of him they wickedly point to is notably foreign, while this is Arabic, pure and clear. (16:103)

Thus have We sent this down - an arabic Qur'an - and explained therein in detail some of the warnings, in order that they may fear God, or that it may cause their remembrance (of Him). (20:113)

In the perspicuous Arabic tongue. (26:195)

(It is) a Qur'an in Arabic, without any crookedness (therein): in order that they may guard against Evil. (39:28)

A Book, whereof the verses are explained in detail;- a Qur'an in Arabic, for people who understand;- (41:3)

We have made it a Qur'an in Arabic, that ye may be able to understand (and learn wisdom). (43:3)

Verily, We have made this (Qur'an) easy, in thy tongue, in order that they may give heed. (44:58)