Tenn. Code Ann. § 58-1-211

Every commissioned officer shall take and subscribe to the oath of office prescribed for officers of the national guard by the applicable laws of the United States and regulations issued pursuant thereto, and to parts 1, 2 and 4-6 of this chapter. Such oath shall be taken and subscribed before an officer of the national guard authorized to administer oaths as provided in parts 1, 2 and 4-6 of this chapter, or before a notary public or other officer authorized by the laws of this state to administer oaths.