Before entering upon his official duties, each commissioner of a drainage district created under this Part shall take and subscribe to an oath before an officer authorized by law to administer oaths, that he will honestly, faithfully, and impartially perform the duties devolving upon him as a commissioner of the drainage district in which he was appointed, and that he will not neglect any of the duties imposed upon him by this Part.  The oaths of the commissioners shall be recorded in the record book of the drainage district.