Louisiana constitution
Article 10
Section 30

Every official shall take the following oath or affirmation: "I, . . ., do solemnly swear (or affirm) that I will support the constitution and laws of the United States and the constitution and laws of this state and that I will faithfully and impartially discharge and perform all the duties incumbent upon me as . . ., according to the best of my ability and understanding, so help me God."