I am assuming you are speaking to the Catholic form of confession, or some form of traditional orthodoxy, which I myself am not familiar to, but I imagine the problem, the fear itself, arises from admitting wrongdoing to someone there and then, in the first person and who "knows" you the individual. The latent, underlying admission of guilt to another carries some sort of threat to it, that reprimand or punishment for it could be carried out, even if the idea is that it is an act of repentance. That is also ignoring that it is of course a frightening experience to confront one's own errors; people have enough issue with that as it is.

Speaking for myself, I have no real regrets or pangs of guilt that hang over me. Confessing an error or wrongful way is not that intimidating; it has already been rationalized and understood for where I erred in it. I know the consequences and weight of my actions, perhaps even knew them fully going in, and that in the end there is no point in having fear or not being at peace with things. No unfinished business.

Speaking on to stranger, more metaphysical and spiritual levels, have you ever experienced any moment where no amount of rationale, logic, reason, or understanding can explain an outcome for you? If so, what transpired? What made it break the apparent rules?