(Church of the Nativity, Jerusalem)
At the heart of the atoning death of Christ on a cross is the concept of substitution. New Testament scholar Simon Gathercole writes:
"The miracle of the gospel is that this link between our sin and our death has been broken. Christ died for our sins. Substitution is there at the heart of the gospel. Christ died so that we don't need to die. Christ bore our sins so that we don't need to bear them."
(From Simon Gathercole and N.T. Wright, What Did the Cross Accomplish: A Conversation About the Atonement.)