All your scholarship, all your study of Shakespeare and Wordsworth would be in vain, if at the same time you do not build your character, and attain mastery over your thoughts and actions.
A clean confession combined with a promise never to commit the sin again, when offered before one who has the right to receive it, is the purest type of repentance.
It is also a warning. It is a warning that, if nobody reads the writing on the wall, man will be reduced to the state of the beast, whom he is shaming by his manners.