The Resurrection, as earliest proclaimed and understood about the year 50 AD. was a moment of motivation where Jesus was raised up on the 3rd day leaving an empty tomb and the early Jesus movement regrouped in Galilee and begun again their social movement for equality with an idea of Jesus alive in them. The movement was always a threat to Rome who in an effort to stop the uprising executed Jesus about 35 AD. Their thought was "kill the leader-kills the movement". This was the understanding of the Jesus Movement up until the Fall of the Temple in 70 AD.
After the fall of the Temple, the Jews and the Early Christians were in chaos and thought that God had abandoned them due to their sins and allowed the Romans to remove His presence-the Temple from them. They felt, as did all other ancient peoples that a god or gods had to be appeased so that sins could be atoned and people forgiven. All illness, catastrophes and calamities were because of the original sin-fall of man from the Garden of Eden. To re-establish relationship, God demanded sacrifice. This gave rise to the need for atonement. By the end of the first century, Jesus had become the great sacrifice for all time who was resuscitated to demonstrate he was the true lamb of God. This was a metaphorical belief held about the year 100 AD as reflected in John's Gospel after most who had experienced Jesus in Galilee had died.
Today we know better! There is not a Judgmental God over us who sends illness to us due to sin. We understand the workings of our solar system and know more about the universe. We are not constantly being watched and judged. God is not there to destroy us but loves us from the start of the Creation of the Universe. We and all people and other life of the planet and the universe are loved and not judged. We don't have to appease God who picks on our individual lives, failings, and situations. Atonement theology denies a loving God and is not a worthy belief for a Progressive Christian in 2018.
God calls us to a journey of wholeness and completeness in love. We do not have to live our lives in shame and guilt always expecting judgment and seeking to atone a vengeful God. Jesus is the "Life of God" living then and living now calling us to live fully, the "love of God" freeing us to love fully, being the "divinity of God" giving us the courage to be all that we can be in 2018 as we speak truth to power and stand up against social inequities as we build a Heavenly Community now on Earth that sustains life forever.