On this day we commemorate the day when the Christ, the Lord of all, vanquished the power of death for all. Death was Satan's final stronghold, and man's final obstacle, and it was defeated on that first Easter morn.
Jesus in the Gospel of John states: "For God loved the world in this way, namely, that He gave His only Son." By giving Himself over to the hands of men, God submitted himself to the unjust and unfair treatment of men. In so doing, he answered those who would claim that because of the evils of this world, God could not exist. He experienced the unjustness they claim is inherent in the world--He experienced Himself the sort of unjustified and senseless suffering that we often stumble over. Yet Christ overcame the power of death and sin--the senseless and cruel evils of this world are not strong enough to overpower the light of the goodness and glory of God, goodness and glory which are manifested in the redemption which Christ completed on Easter morning.
Christ has shown to us the path which we all must travel. Nietsche thought that what didn't kill him would strengthen him. Christ reveals that strength is available only through the dying and rising again, a process which we celebrate on this happy Easter day.