An-Nisa 4:49

Alam tara ila allatheenayuzakkoona anfusahum bali Allahu yuzakkee man yashaowala yuthlamoona fateela

Have you not seen those who claim themselves to be pure? Rather, Allāh purifies whom He wills, and injustice is not done to them, [even] as much as a thread [inside a date seed].

Have you not seen those who claim sanctity for themselves? In fact, Allah sanctifies whom He wills, and they shall not be wronged even to the measure of a thread of a date-stone.