I suppose we should start at the beginning then.
As I said, Satanic "sins" essentially fall into two categories:
- Things that go strictly against Satanic doctrine. Examples would be unnecessarily harming animals, breaking laws, using drugs, etc. The reaction of other Satanist and the CoS itself to these acts would generally be rather severe. So far as "confession" goes I encourage anyone who does this to confess right away so we can be rid of them. They don't belong, confession or no.
Of note, Satanists really need not worry about this kind of "sin" because all of them are things that any decent human being will not find themselves doing.
- Actions that betray one's self. Several of the Satanic Sins listed by Dr. LaVey are of this nature. The important thing to note about most of these is that the primary person hurt by them is yourself. Counter-productive pride may make those around you miserable, but the one who truly suffers will be you, which is why it is a Satanic sin in the first place.
These are not things that will necessarily result in expulsion, assuming the person in question corrects the issue or limits the damage done to themself only. Continued transgression of a nature that reflects badly on us all or brings you into conflict with the Church will of course result in action taken.
As for "confession"...it does not really apply. It may be useful or important to admit to the mistake made, if for example your mistake has involved others, then obviously correcting that can go a long way. As you mentioned, the operative concept here is "Did you learn from the mistake?" Confession implies need for forgiveness from a higher power, which is not a concept compatable with Satanism. It is also worth noting that any such admission and forgiveness is a personal matter between the parties involved.
Confession also implies that even if you are able to keep the mistake to yourself, it should be admitted to others. I do not see it that way. If you screwed up and nobody has to know, then fix it and move on. Simple as that.
Confessors are usually attention seekers. Nothing more and nothing less. What they truly crave is pity for their pitiful life, and there is a short supply of that indeed among Satanists.
"The devil I'll bring you," answered Hagen. "I have enough to carry with my shield and breastplate; my helm is bright, the sword is in my hand, therefore I bring you naught."