The rule is designed to afford the flexibility required in dealing with religious adults, atheists, conscientious objectors, mental defectives, and children. Affirmation is simply a solemn undertaking to tell the truth; no special verbal formula is required. As is true generally, affirmation is recognized by federal law. “Oath” includes affirmation,
1 U.S.C. §
1; judges and clerks may administer oaths and affirmations,
28 U.S.C. §§
459,
953; and affirmations are acceptable in lieu of oaths under Rule 43(d) of the Federal Rules of Civil Procedure. Perjury by a witness is a crime,
18 U.S.C. §
1621.
The amendments are technical. No substantive change is intended.