If any person to whom an oath is lawfully administered on any occasion willfully swears falsely on such occasion touching any material matter or thing, or if a person falsely make oath that any other person is 18 years of age or older in order to obtain a marriage license for such other person, or if any person in any written declaration, certificate, verification, or statement under penalty of perjury pursuant to § 8.01-4.3 willfully subscribes as true any material matter which he does not believe is true, he is guilty of perjury, punishable as a Class 5 felony. Upon the conviction of any person for perjury, such person thereby shall be adjudged forever incapable of holding any office of honor, profit or trust under the Constitution of Virginia, or of serving as a juror.