Amends section 502 to (1) change wording in former subsection (b) from "The oath" to "An oath established by this section," (2) redesignate subsection (b), as amended, as subsection (c), (3) insert a new subsection (b) establishing a separation oath to be taken prior to retirement or other separation (other than pursuant to a court-martial), and (4) amend the section heading and the table of sections to reflect an enlistment oath and separation oath and who may administer them.