Verily, those who divide their religion and break up into sects (all kinds of religious sects), you (O Muhammad ﷺ) have no concern in them in the least. Their affair is only with Allah, Who then will tell them what they used to do.

Of those who split up their religion (i.e. who left the true Islamic Monotheism), and became sects, [i.e. they invented new things in the religion (Bid'ah), and followed their vain desires], each sect rejoicing in that which is with it.

He (Allah) has ordained for you the same religion (Islam) which He ordained for Nuh (Noah), and that which We have inspired in you (O Muhammad ﷺ), and that which We ordained for Ibrahim (Abraham), Musa (Moses) and 'Iesa (Jesus) saying you should establish religion (i.e. to do what it orders you to do practically), and make no divisions in it (religion) (i.e. various sects in religion). Intolerable for the Mushrikun, is that to which you (O Muhammad ﷺ) call them. Allah chooses for Himself whom He wills, and guides unto Himself who turns to Him in repentance and in obedience.