The following is attributed to Rav Adda: "The man who is conscious of sin and confesses it, but does not turn away from it, is like the man who holds a defiling reptile in his hand; were he to bathe in all the waters of the world, the bath would not restore him to cleanness.
Rav Adda stated that a person who recognizes their sin and confesses it but fails to repent remains as dirty as someone carrying an unclean reptile. No amount of bathing would cleanse him completely.