It is reported that Sufyān Al-Thawrī – Allāh have mercy on him – said, “Wealth is the disease of this Ummah, and the scholar is the doctor of this Ummah. So if the doctor brings the disease to himself, how will he cure the people?”
Al-Dhahabī, Siyar A’lām Al-Nubalā`, Vol. 7 p243.