A Marriage Affidavit is a sworn statement affirming the date and validity of a marriage. To make a sworn statement, you ordinarily present yourself first and after that swear that you will come clean in the testimony.Learn how to complete a marriage affidavit template with our stepbystep guide for newlyweds. The forms below are some of the most common forms used in the Domestic Relations Division, but there are many more. Illinois Legal Aid Online provides a guided interview called an Easy Form that will help you fill out the forms. Your statement of freedom to marry, given under oath in front of a notary public, is considered to be a single status affidavit. If you fill out a form on a webpage, you will lose your progress. An I751 affidavit can be an essential component in proving the legitimacy of your marriage. It's a sworn statement to prove a marriage took place if a couple misplaces their copy of a marriage certificate. Administering an oath or affirmation is an important role of a Notary.