Quran

This is the greatest blessing that Allah has bestowed upon His servants, that He has prescribed for them the best and purest of religions, namely the religion of Islam, which Allah has prescribed for the chosen ones among His servants. Indeed, Allah prescribed it for the best of the best, the elite of the elite, namely the Messengers of firm resolve who are mentioned in this verse, who are the highest of humankind in status and the most perfect in all aspects. Al-Saadi: 754.
Question: What is Allah's greatest blessing upon you?

The religion of our Prophet Muhammad (ﷺ) is in accordance with all the prophets in the fundamentals of faith, that is the meaning of this verse. Hence, Allah explains it by saying, (to establish the religion), which means Islam, the Oneness of Allah, obedience to Him, believing in His Messengers, Books, and the Hereafter. As for the minor rulings, each Sharia has its own, and that is not what is meant by this verse. Ibn Juzay: 2/299.
Question: What are the things that the Prophets' Messages have in common? What are the things that they differ about?

Allah has sent all the Prophets to establish religion, harmony, and unity, and discard division and discord. Al-Baghawi: 4/77.
Question: This verse presents a common objective with which all Prophets were sent. What is it?

Meaning: It is hard for them (that to which you invite them), which is the Oneness of Allah and rejection of idols. Qatadah said: Testifying to the Oneness of Allah was difficult for the polytheists, and Iblees and his soldiers were distressed because of it, but Allah refused except to raise it high and empower it over those who opposed it. Al-Qurtubi: 18/453.
Question: The polytheists faced a difficult matter. What was it?

The division among them was not due to unclarity of proof, rather, the animosity between them was due to fighting over headship, transgression, and pursing worldly gains. Al-Qurtubi: 18/454.
Question: What is the reason for the division among eminent Muslims despite the availability of knowledge?

Having commanded the Muslims to be united in their religion, and forbidden them from being divided, Allah informs them that they should not take it for granted that they will remain united just because Allah has sent down the Book to them, for the People of the Book did not become divided until Allah sent down to them the Book that required them to be united. Al-Saadi: 755.
Question: What is the useful lesson that we draw from being informed about the people of the Book?

Allah did not say "do not follow their religion" because their original religion, which Allah had prescribed for them, was the religion of all the Messengers, but they did not follow it; rather they followed their whims and desires and they took their religion as a mockery and a mere game. Al-Saadi: 755.
Question: This verse cautions against the risk of innovation in religion. Explain.