An Oath (n.) is kept by what you meant, not what you said: the man who went back to camp for something forgotten was acquitted in words alone.
An Oath (n.) is judged not by what it threatens but by what it means: it is a religious affirmation, and the question concerns honesty and good faith, not the anger of the gods.
An Oath (n.) profaned profanes Faith, whom our ancestors chose to have in the Capitol, hard by the shrine of Jupiter Best and Greatest.
An Oath (n.) can be sworn in words and unsworn in mind: "I swore in words; my mind I keep unsworn."
An Oath (n.) could be forced at sword-point: Titus Manlius drew his sword at dawn on a tribune and made him swear to drop the prosecution of Manlius's father, and the tribune kept the oath.