Also, Rassah, you mentioned that you felt offended because God forgives people without consideration of the victim of the crime, this is because in committing a crime someone has offended 3 entities:
1. A Holy and just God
2. The victim
3. The law
One may have forgiveness from you and God, and yet still rightfully go to jail, and people may still ask for forgiveness from God, with the realization that the they have not been given forgiveness from the victim.
So... why did got have to sacrifice himself to himself on a cross to forgive us? And in a way that wasn't even much of a sacrifice, since he knew he would be resurrected and come to sit with himself a few days later...
You have to understand what death is... In God's presence, all is sustained. Without, all is subject to death and decay. God, the absolute authority, cannot justly tolerate disobedience therefore the wages of sin is death. Christ did not sin, and yet was subject to death. He was forsaken that dark day, as far as his human frame could tell. It was an infinite injustice, yet by it we are "in" him eternally. He was made responsible for our sin, bearing the consequences so that all who are in him could be spared. The passover atonement was established as a pattern for thousands of years prior, and was absolutely necessary for anyone to be able to come before God, as we do now. He was the lamb of God, and from our angle, is all of God that we can see, God with Us.