The ransom theory present Jesus as dying to overcome (supernatural) powers of sin and evil. In this model, the Devil has ownership over humanity (because they have sinned) so Jesus dies in their place to free them. The doctrine is that Jesus gave himself as a ransom sacrifice on behalf of the people. This is known as the oldest of the theories of the atonement, and is, in some form, still, along with the doctrine of theosis, the Eastern Orthodox Church's main theory of the atonement.