Tafsir of Al-An'am 6:66

(And have denied it) – meaning the Qur’an, as Al-Azhari said, and it is narrated from Al-Hasan. It has been said: the pronoun refers to the 'explaining of the signs,' and this was chosen by Al-Jubba'i and Al-Balkhi. It has also been said: it refers to the punishment, which is the choice of most exegetes. (Your people) – meaning the Quraish. It has been said: they are they and the rest of the Arabs. Regardless, the intent is the obstinate ones among them. Perhaps their being mentioned with this title [your people] is to signal the extremity of their wretched state, for their denial of it, despite being from his people—peace and blessings be upon him—is something that necessitates the utmost of their arrogance and defiance. The prepositional phrase is placed before the agent [in the Arabic structure] for reasons previously mentioned time and again.

(And it is the truth) – meaning the book that is truthful in everything it speaks of, in which there is no doubt; or the one whose indication is verified; or that which will inevitably come to pass. The 'waw' is for a circumstantial state (hal), and the sentence following it is in the place of a circumstantial state for the genitive pronoun. It has been said: the 'waw' is for commencement, and what follows it is an independent sentence. Regardless, it contains an indication of the magnitude of their crime and the extremity of its ugliness.

(Say: I am not a guardian over you) – meaning: I am not a trustee entrusted with your affairs so that I might record your deeds to reward you for them. I am only a warner, and I have not spared any effort in warning; Allah, the Glorified, is the One who recompenses. This was said by Al-Hasan.

Al-Zajjaj said: The meaning is that I have not been commanded to wage war against you or to forcibly prevent you from denial. Similar in meaning is what has been transmitted from Al-Jubba'i. According to a narration from Ibn Abbas—may Allah be pleased with them both—the verse is abrogated by the Verse of Fighting, and there is nothing far-fetched in that concerning the second interpretation.