Kilab bin Umayyah (may Allah have mercy on him) narrates that he met Sayyiduna Uthman bin Abi al-As (may Allah be pleased with him), who asked: "What has brought you?" He said: "I have been appointed over (collecting) the tithe ('ushr) of al-Ubullah." Sayyiduna Uthman (may Allah be pleased with him) said: I heard the Messenger of Allah (peace and blessings be upon him) say: "Allah Almighty draws near to His creation and forgives whoever seeks forgiveness, except an adulteress (who persists in earning) through her private parts, or a tithe-collector (an oppressive official)."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 8339