Confession (n.) has to confess its own narcissism — admitting that guilt, even the lie, is lodged inside veracity itself.
A Confession (n.) can be a confession without confession: I tell you that I cannot tell you, and that is the first crime and the first confession.
A Confession (n.) without repentance or mercy can be a provocation: perhaps the friend gave the false coin only so as to confess it to his companion.
Confession (n.) is not giving information: its purity shows best when the other already knows — which is why Augustine confesses to a God who knows everything.
A Confession (n.) can be counterfeit too: the friend who says "it was the counterfeit coin" may be passing true money off as false.