N.C. Gen. Stat. § 28A-7-1: Oath required before letters issue.

Before letters testamentary, letters of administration or letters of collection are issued to any person, the person shall take and subscribe an oath or affirmation before the clerk of superior court, or before any other officer of any state or country authorized by the laws of North Carolina to administer oaths, that the person will faithfully and honestly discharge the duties of the person's office. Such oath or affirmation shall be in the form prescribed in G.S. 11-11, and shall be filed in the office of the clerk of superior court. (C.C.P., ss. 467, 468; 1870-1, c. 93; Code, ss. 1387, 1388, 2169; Rev., s. 29; C.S., s. 39; 1923, c. 56; 1967, c. 41, s. 1; 1973, c. 1329, s. 3; 2011-344, s. 4.)