The Idea of Absolution.
I was brought up in the Lutheran denomination. In many ways, I view this faith as Christianity-lite. It seemed to have been more about the community of the church than anything else. As long as you accepted the idea that Christ died for your sins, then you were assured a place in heaven. You didn't have to get born again. You didn't have to atone for your sins. And there were no intermediaries. I suppose that is why the number of Lutherans in the world is decreasing. There isn't a whole lot to compel followers to stick with it. Maybe it would have been more effective if the pastor would have talked more about the state of the soul in hell. Without guilt, shame, original sin, confession, and the priestly hierarchy... there's just not a whole lot to grab onto.
Catholics, on the other hand, rarely seem to let their upbringings go. All my friends who grew up in this religion appear to have considered it a necessity to define themselves according to Catholicism. Either they still consider themselves active adherents, or they outright reject it (and tend to extrapolate this position to all religion). I've met more than a couple of ex-Catholics that actively oppose the idea of faith. There is a lot to be processed- the lives of the saints, relics, Mother Mary, along with the things I mentioned above. Catholicism has got so much ritual and trappings that I can understand why people build their lives around it. I'm fascinated by the iconography, the fancy costumes, the incense, and the Latin Mass. But I can afford to appreciate it from an objective perspective. Prior initiates don't seem to have been granted that latitude.
Perhaps the most perplexing aspect of Catholicism (to a young Protestant) is the idea of confession. All humans are sinners and carry the weight of their deeds with them in every facet of life. The early Roman Catholic church fathers were very wise to set themselves up as the middlemen between their followers and God. Not only did they become indispensable in their ability to grant absolution, but they also got to hear all of the secrets of the community. This certainly made them highly revered and quite powerful. There is a very clear power structure set up through this mechanism.
I always found it wondrous that my friends would go into a little fancy box, and relate their innermost shames to another human through a screen. Apparently the priests are serving in their capacity as representatives of the Almighty Himself. So you really aren't sharing your dirt with a human authority figure at all. You're just passing the message along. You are admitting that you are bad, and in doing so you get forgiveness and a clearer path to Heaven. Not a bad system, really. Guilt can be a very powerful obstruction to an effective lifestyle. I have to think that the early psychotherapists used confession as a model for their practices.
Yet we all know that human beings are imperfect, and ultimately those priests are merely men. So it takes a tremendous amount of trust to believe that you are not going to be betrayed after you admit to your misdeeds. A sacred confidentiality is a necessary assumption in building the confidence of the participants. If the seal is violated, then surely people will stop participating in confession. The priest holds the key to something the faithful want- forgiveness. Although I don't know this from experience, I gather that the priests can withhold absolution if they do not believe that the confessor is sincere in his/her wish for atonement. This would suggest that personal judgment does indeed come into play. Meanwhile you would have to wonder why someone would admit to committing a crime if they did not truly have faith in the entire process. It makes me wonder how many unsolved crimes could be cleared up if the priests were allowed to consult with the police. But we wouldn't want to mix the holy with the profane, would we?