Surah Ash-Shuraa, Verse 8

وَلَوۡ شَآءَ ٱللَّهُ لَجَعَلَهُمۡ أُمَّةٗ وَٰحِدَةٗ وَلَٰكِن يُدۡخِلُ مَن يَشَآءُ فِي رَحۡمَتِهِۦۚ وَٱلظَّٰلِمُونَ مَا لَهُم مِّن وَلِيّٖ وَلَا نَصِيرٍ٨

walaw shāa l-lahu lajaʿalahum ummatan wāḥidatan walākin yud'khilu man yashāu fī raḥmatihi wal-ẓālimūna mā lahum min waliyyin walā naṣīrin

And if Allāh willed, He could have made them [of] one religion, but He admits whom He wills into His mercy. And the wrongdoers have not any protector or helper.