Jesus died on he cross so that we can live? Can there be anything less logical than that statement?
First, if God has a loving and forgiving nature, why should He need to make a human sacrifice of His Son to 'save' us?
Second, if Jesus was God in human form, as Christians believe, then why should Jesus say on the cross "My God, My God, why hast Thou forsaken me?" (Matt. 27:46) Had Jesus lost faith in God ... err... Himself? That makes no sense either.
And here's another conundrum: How can Jesus' death, 2,000 years ago, take away sin that's around today? Let's suppose it's true that 2,000 years ago, the death of Jesus could take away or forgive existing sin and even past sin. But take away future sin? This is making less sense by the minute!
Well, for answers, try this:
Let's look at who we are, or rather what we are. Think of our physical body. It gets born, grows up a little, dies, then breaks into little bits of nothingness. But our body is not who we are - it's just a physical house we live in and from which we can operate our five senses1.
In addition to the body, we have this special entity - the thing that makes the body into a person. Let's for sake of argument, call that entity the soul. This is made up of things like thought, emotion, ambition, will, moral reasoning - all things that are not physical but are obviously connected to our physical bodies. The soul does not break into little bits of nothingness when the host dies, since it has no physical substance in the first place, and so it exists after physical death, in our post-human state (whatever that is).
Then there's one more part of us, also non-physical, called the spirit. With the spirit, we can communicate beyond our physical world - with the spirit, we can communicate with God.
So, who are we? We are a soul, we have a spirit, and we live in a body2.
Well that's all very nice, but if our spirit is weighted down with sin, then we are separated from God. God is perfect and as such, sin is repelled away from God. If we want eternal life with God (and remember - our soul is an eternal entity) then we must dump this sin. The alternative is too horrible to contemplate.
As we noted above, God is a loving God. He could easily prevent our spiritual death - God is God, so He can do absolutely anything He wishes. And what He wishes is this: God has given us freedom, freedom to choose; loving Him or disobeying Him. If we choose to disobey Him, that is our choice. And we must pay the penalty, which is spiritual death (separation from God). If God just overlooked man's sin, this would take away man's freedom and we would be not human.
And this is where the cross comes into the story. When Jesus was being crucified, God reached back in time, way back, (and I mean really way back, to about the time of Adam, when there was a guy named... errr ... Adam.) Anyway, about 2,000 years ago, God took the sin, the spiritual death, that had been generated by Adam and everyone who had lived after Adam. God also reached forward in time, and took away the sin that would occur after Jesus' Crucifixion. (Remember that 'time', 'past' and 'future', are only concepts that we humans live with. In eternity - God's realm - there is obviously no such thing as 'time'.) God placed this spiritual death on Jesus on the cross.
Little wonder then that Jesus cried, "My God, My God, why hast thou forsaken Me?" He was enduring the spiritual death created by billions of people - every human that ever has existed and who will exist. In bearing this spiritual death, Jesus was disconnected from God whilst He was on the cross.
That's a pretty awesome deed, and remember - God did this for us because He loves us. If we simply ask Jesus to take our sin, on the cross, He will. It's a free gift, already paid for. If we accept it, we will enjoy everlasting life with God.
Whether we accept it, is entirely up to us.