There are occasions and events that try to mark genuinely radical turning points that sit above everyday life: someone has just arrived on the planet;
somebody has just left it; a child is turning into an adult....
This is not the everyday.
In a marriage ceremony, you are trying on a single day, at a single instant,
to commit yourself to another person for the rest of your existence.
The event is trying to make an extraordinary leap:
to take us out of normal time
and put us in touch with something close to eternal.
It is trying to defy the ordinary flux of experience in which circumstances change constantly
and passing whims and fancies enjoy complete sway,
and shepherd us towards a commitment that will last until we are laid out in the grave.