The Christian faith centers around the person of Jesus of Nazareth whom Christians believe was the Christ or the son of God. My first problem with Christianity is that I'm not convinced that Jesus was the Christ, or that there is even such a thing as a Christ. But that's not what I don't "get" about Christianity. That's just my own personal crisis of faith. I understand that.
What I don't "get" about Christianity is that its central tenet makes no logical sense to me at all. The central tenet of Christianity is that Jesus, being the Christ, accepted suffering and death at the hands of ordinary men in order to atone for the sins of mankind. Mankind had sinned against God through the ages, over and over again, and that opened up a rift between God and mankind. In order for mankind to be reconciled with God and brought back into His good graces, an atonement was necessary. Somebody had to pay the price for all that sinning. So God made His only Son incarnate, one of us, and He took it upon Himself to pay the price that God exacted for our sins, and so redeemed us. And not just up to that point, but forever thereafter. I mean, sadly, people haven't stopped sinning since Jesus allegedly rose from the dead but apparently all those sins committed since then, and forever on into the future, are still forgiven as well, thanks to Jesus.
I imagine that any Christian, having read this far, is probably scratching their head thinking "That's exactly right! So what don't you get (aside from doubting Jesus' divinity and that snarky use of the word 'allegedly' with regard to His resurrection?)"
Okay, let's take God out of the picture for a moment and let's look at a similar scenario in human terms. Imagine that a couple of guys break into your house, take all your most valued belongings and vandalize the place, not to mention scaring the bejeebers out of your wife and kids. They have sinned against you. They've done you wrong and, if brought to justice, the law would surely demand some kind of atonement from them.
Now let's say that you find out who they are but, rather than call the police, you send your only son to talk to them, open their eyes, teach them the error of their ways and maybe inspire a little remorse.. Well, not only do they not listen to him nor show any remorse, but they call the police themselves and report him for trespassing. The police arrive, arrest your son, and put him in jail.
There. All good now, right? Their debt has been paid and their sins are forgiven. Not just the break and enter perpetrated in the past but, should they do it again, that's forgiven too.
No, it's not all good of course. How does punishing your blameless son for the wrongs perpetrated against you make anything right? I simply cannot reconcile that logic in my own mind.
Ironically, it would make more sense to me if we discarded the notion of Jesus' divinity. If he were just an ordinary (or make that extraordinary) man, but not any kind of deity, then he becomes one of us and he accepts the punishment exacted by God on everyone else's behalf. Now, that's noble and that begins to make some sense. Maybe in so doing he shows God that not all men are evil and restores His faith in His own creation, thus reconciling God and man. I understand that devout Christians will still have a huge problem with this kind of thinking, but at least it begins to make some sense to us not-so-devout people.