Every committed Muslim should have a firm belief that Allah Almighty is UNIQUE in everything. The Qur’an, which is Allah’s speech, is the best example of eloquence and perfection. The usage of the pronouns “I, We, He” as referring to Almighty Allah in the Qur’an is a variation in style of address which serves rhetorical purposes and is considered a sign of the eloquence of the Qur’an as far as the Arabic language is concerned.
The Whole Qur’an is Allah’s words; there is no doubt in that. When the Qur’an was revealed, the pagan Arabs who were distinguished by their eloquence at that time were challenged to come with even a single surah like any of the surahs of the Qur’an but they could not. Had they seen any mistake or a sign of non-eloquence in the Qur’an they would have hastened to criticize it. On the contrary, many of the pagan Arabs like Al-Walid ibn Al-Mughirah praised the eloquence of the Qur’an despite his (Al-Walid) disbelief.