Chapter 1: Purpose and Background
Before becoming a United States citizen, an eligible naturalization applicant must take an oath of renunciation and allegiance (Oath of Allegiance) in a public ceremony.  See INA 337. See 8 CFR 337.1(a). The applicant must establish that it is his or her intention, in good faith, to assume and discharge the obligations of the Oath of Allegiance.  See INA 337. See 8 CFR 337.1(c). Under certain circumstances, an “Affirmation of Allegiance” is the same as an Oath of Allegiance. See 8 CFR 337.1(b). The applicant must also establish that his or her attitude toward the Constitution and laws of the United States makes the applicant capable of fulfilling the obligations of the oath.  See 8 CFR 337.1(c).
During the naturalization interview, the applicant signs the naturalization application to acknowledge his or her willingness and ability to take the Oath of Allegiance and to accept certain obligations of United States citizenship. Under certain circumstances, an applicant may qualify for a modification or waiver of the oath.  See Chapter 3, Oath of Allegiance Modifications and Waivers [12 USCIS-PM J.3]. In such cases, an officer draws a line through the designated modified portions of the oath and the applicant is not required to recite the deleted portions.  See 8 CFR 337.1(b).
Applicants must generally recite the Oath of Allegiance orally during a public ceremony. Merely signing the naturalization application and a copy of the oath does not make the applicant a U.S. citizen.
C. Legal Authorities
Public Law 106-448 – Waiver of Oath of Renunciation and Allegiance for Naturalization of Aliens having Certain Disabilities Act of 2000