Notes of Advisory Committee on Rules
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.