The auditor shall, before entering upon the duties of his office, take and subscribe to an oath endorsed on his certificate of election that he will support the Constitution of the United States and of the state of Missouri, and faithfully and impartially discharge all the duties of his office; which certificate and the oath of office endorsed thereon shall be recorded in the recorder's office of the county and then deposited and safely kept in the office of the clerk of the county commission.
§ 55.080, RSMo