And We had already given Moses the Scripture, but it came under disagreement.1 And if not for a word [i.e., decree]2 that preceded from your Lord, it would have been concluded between them. And indeed they are, concerning it [i.e., the Qur’ān], in disquieting doubt.
Translation: Saheeh International (English)
1 An alternative meaning is "he was opposed over it."
Verily I gave Moses the Torah and it was disagreed upon. Some believed in it, while others disbelieved in it. Had there not been a promise from Me that there will be judgement passed between the servants on the Day of Judgement in matters they disputed over, judgement would already have been passed upon those who disputed in the Torah. I would have made the ones on the truth clear from those on falsehood and honoured those on the truth whilst disgracing those on falsehood. Indeed, the disbelievers are definitely in suspicious doubts with regards the Qur’ān.