Definition.com
The Oath is better never to be taken, for when you do, people tend to think you mean it.
Definition.com
An Oath is a recognizance to heaven, binding us over in the courts above to plead to the indictment of our crimes.
Definition.com
An Oath is a thing which to sign is to destroy some of the loyalty one could otherwise claim, since any subsequent loyal behavior may then be attributed to the oath.