Ash-Shura: 13
{He has ordained for you of religion}
The religion of Noah, Muhammad, and the prophets between them. He then explains the "ordained matter" in which these prominent messengers shared by saying: {that you establish the religion and do not be divided therein}.
The intent is the establishment of the religion of Islam, which is the oneness of God (Tawhid), obedience to Him, belief in His messengers, His books, and the Day of Recompense, along with everything that makes a person a Muslim by establishing it. He did not mean the specific laws (shara'i') that serve the interests of nations according to their varying circumstances, for those are different and diverse, as God Almighty said: "To each of you We prescribed a law and a method" (Al-Ma'idah: 48).
The grammatical position of {that you establish} is either in the accusative as a substitute for the object of "ordained" and what is conjoined to it, or in the nominative as an initiation (new sentence), as if it were asked: "What is that which is ordained?" and the answer was: "It is the establishment of the religion." Similar to His saying: "Indeed, this, your religion, is one religion" (Al-Anbiya: 92).
{It is difficult for the polytheists}
It is burdensome and hard upon them.
{that to which you invite them}
Namely, the establishment of the religion of God and monotheism.
{He chooses for Himself}
He draws to Himself and gathers. The pronoun refers to the religion, through success and guidance.
{whom He wills}
Those in whom His success is beneficial and upon whom His grace flows.
{And they did not become divided except after knowledge had come to them - out of jealous animosity among themselves. And if not for a word that preceded from your Lord until a specified term, it would have been concluded between them. And indeed, those who were granted inheritance of the Scripture after them are, concerning it, in disquieting doubt.}
