Haven't you ever come across someone who is basically gossiping about another Christian? Gleefully recounting sin? Is it right for a person to go to half the church or study group or friends and tell them about another's mistake...breaking confidence to do so...using that information to hurt? Even if the other had in fact sinned, as Christians, do we kick them while they're down, or do we help them up? If the other person is already aware of their mistake, how do we see the benefit of revelling in that mistake, making it fodder for gossip and our own self righteousness..."look how bad they are, thank goodness I'm not like them"? If the person repents and moves on, shouldn't we too?
I just think we see it too often, is all. Haven't you seen it?
OH! Sorry, I didn't get it from the OP. I thought you might be talking about someone specific. In that case....Carry on.

Seriously, though...Yes I DO know exactly what you are talking about and IMO...It is disgusting behavior.