4:49
أَلَمْ تَرَ إِلَى ٱلَّذِينَ يُزَكُّونَ أَنفُسَهُم ۚ بَلِ ٱللَّهُ يُزَكِّى مَن يَشَآءُ وَلَا يُظْلَمُونَ فَتِيلًا
alam tara ilā alladhīna yuzakkūna anfusahum bali l-lahu yuzakkī man yashāu walā yuẓ'lamūna fatīlan
[Prophet], have you considered those who claim purity for themselves? No! God purifies whoever He will: no one will be wronged by as much as the husk of a date stone.
Have you not seen those (Jews and Christians) who claim sanctity for themselves. Nay, but Allâh sanctifies whom He wills, and they will not be dealt with injustice even equal to the extent of a scalish thread in the long slit of a date-stone.