He, Exalted is He, has also said:

“We surely granted the Children of Israel the Scripture, sound judgment, and prophethood. We provided them with wholesome provisions and favored them above all peoples. We gave them clear proofs concerning the faith, yet they did not differ until after knowledge had come to them, out of mutual envy. Your Lord will judge between them on the Day of Resurrection regarding that over which they differed. Then We set you upon a clear law of the religion, so follow it, and do not follow the desires of those who lack knowledge. They can avail you nothing against Allah. Indeed, the wrongdoers are allies of one another, but Allah is the Guardian of the God-fearing.”
(Qur’an, al-Jāthiyah 16–19)

The unqualified form of disagreement that Allah condemns in the Qur’an is when every faction invents a doctrine that blends truth with falsehood, so that each group opposes and shows hostility toward the others while all of them diverge from the religion of Islam with which Allah sent the messengers—such as the dispute of the Jews and Christians over the Messiah and other matters, or the divisions spawned by the people of vain desires within this very community.