It is quite clear that without the belief in the resurrection the Christian faith could not have come into being. The disciples would have remained crushed and defeated men. Even had they continued to remember Jesus as their believed teacher, His crucifixion would have forever silenced any hopes of His being the Messiah. The cross could have remained the sad and shameful end to His career. The origin of Christianity therefore hinges on the belief of the early disciples that God had raised Jesus from the dead.
William Lane Craig. The Son Rises: The Historical Evidence for the Resurrection of Jesus.