Full Idea
Repentance and reformation can wipe off every crime, but that is because criminal acts prove criminal principles in the mind, so alteration of these principles removes that proof, and the acts cease to be criminal.
Gist of Idea
Repentance gets rid of guilt, which shows that responsibility arose from the criminal principles in the mind
Source
David Hume (Enquiry Conc Human Understanding [1748], VIII.I.76)
Book Reference
Hume,David: 'Enquiries Conc. Human Understanding, Morals', ed/tr. Selby-Bigge/Nidditch [OUP 1975], p.99
A Reaction
A bit overstated, because a heinous crime will always taint our impression of someone's character. The person may cease to be criminal, but surely not the original acts?