I answered the following question on Atheist Central and figured that I would cross post on my own blog:
If God forbids human sacrifice, why did he allow Jesus to be a human sacrifice?
Although human sacrifice is wrong, self-sacrifice is the highest virtue. Just about every culture recognizes this, and John 15:13 says, "Greater love has no one than this, that one lay down his life for his friends."
God was not the one who killed his Son on the cross. He simply gave him over to the forces of evil in order to pay our debt, letting evil run its course, and thereby defeating it. When he died, the veil of the temple tore in two, and we can now partake in his victory over sin and death by entering the "Holy of Holies" through faith.
But in addition to the theological significance of the cross, it was a dramatic expression of God's love for his enemies. Before his death, Jesus said, "Father, forgive them for they do not know what they are doing" (Luke 23:34). And 1 Peter 3:18-20 tells us that after his crucifixion, Jesus went straight to the "spirits in prison" who rebelled against him during the days of Noah and died in the flood, and he made his proclamation of peace to them. So the cross was the pinnacle of self-sacrificial love, where the King Kings died willingly between two criminals.
And although God desires all to be saved and come to the knowledge of the truth, each one of us is like one or the other of the criminals. One said, "Are you not the Christ? Save Yourself and us!" But the other said, "Do you not even fear God, since you are under the same sentence of condemnation? And we indeed are suffering justly, for we are receiving what we deserve for our deeds; but this man has done nothing wrong.' And he was saying, 'Jesus, remember me when You come in Your kingdom! And He said to him, 'Truly I say to you, today you shall be with Me in Paradise'" (Luke 23:39-43).