The problem which has come to the surface in the encounter of Christianity with the other world religions is this: If Jesus was literally God incarnate, and if it is by His death alone that men can be saved, and by their response to Him alone that they can appropriate that salvation, then the only doorway to eternal life is the Christian faith.
The Truth of God Incarnate, Eerdmans, 1977), p. 180, www.eerdmans.com.
Christianity does not hold the Resurrection to be one among many tenets of belief. Without faith in the Resurrection there would be no Christianity at all. The Christian church would never have begun; the Jesus-movement would have fizzled out like a damp squib with His execution. Christianity stands or falls with the truth of the Resurrection. Once disprove it, and you have disposed of Christianity.
Man Alive, IVP, 1968, p. 61.