Why did Christ die on the cross? What purpose did it serve?
He died so that we may be free from the bondage (of death). It was a deliverance from death to life. Ergo, the Pascha (Passover), which the West calls by a pagan name Easter.
Christ gave His life to the devil in exchange (ransom), not because He owed the devil but because He willed it out of love for humanity. As St. John Chrysostom said more than 16 centuries ago "death expected Man, and received God." Having no power over God, death could not keep Him and was defeated, while mankind was given a chance to be redeemed through the grace of God by submitting to, following and imitating Christ.
Now, before you all jump on me, this is Orthodox doctrine, as old as the Eastern Church (just about 2 millennia) perhaps not stated eloqunetly, but in a nutshell.
“Why did Christ die on the cross? What purpose did it serve?”
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