In one sense, Jesus did not have to die. He lived a perfect life and did not earn the "wages of sin," which is death.
So then, if Jesus did not have to die, why did he die? I can think of at least two reasons.
First, Jesus died to show us how much he loves us. His death and resurrection showed that he identified with humanity, even in the suffering of the human condition. He wants to be with us, and he was willing to endure hardship beyond our comprehension to do so. In his death, Jesus restored our relationship with God.
Second, Jesus suffered and died to show us the horror of sin. We may consider our sins mild or of little consequence. But we are all bent toward rebellion against God. Selfishness is part of the human condition, just as much as suffering. Jesus's death shows us that sin is no small matter. Our sin is costly in all our relationships. The sickening ordeal of crucifixion, condemnation on false charges, and desertion of friends, helps us understand how damaging our sin is.
The cross is full of meaning and significance. We can spend our whole lives meditating on his sacrificial goodness and never fully grasp his gift of himself.
