إِنَّ هَٰذِهِ أُمَّتُكُمْ أُمَّةً وَاحِدَةً وَأَنَا رَبُّكُمْ فَاعْبُدُونِ

God has sent all prophets with the same religion, namely, one according to which the one and only God should be one’s God and that He alone should be worshipped. Had people been steadfast in this original religion, all of them would have continued as one Community (ummah). But, people on their own started entering into disputes and thus concocted different versions of the same religion. Individuals exercised their ‘right’ to choose whatever religion best suited their interests. Thus one religion came to be divided into many religions. To God, faith and deeds have importance only when they signify true realization of Him and true obedience to Him. Anything other than these will not be appreciated by God, however much the individuals themselves may attach value to them.

— Source: Tazkirul Quran (Maulana Wahiduddin Khan) via Quran.com (21:92)