Atonement

There are many theories about how Jesus' death on the Cross makes reparation for the sins of all mankind.

I think all valid theories have to be some form of vicarious satisfaction.

Jesus acts as the representative (Latin: vicar) of all sinners.

He also acts as God's vicar.

His death is of infinite worth because He is a Divine Person, eternally begotten of the Father from before all time.

His death is a human action because He has a full human nature and is truly human.

His death is a divine action because He participates fully in the Divine nature (homoousios, consubstantial, "one in being" with the Father and the Spirit) and is truly God.

The action of Jesus on the Cross is the action of the Father and the Spirit as well, although only the Son became human and only the Son suffered and died on the Cross. Jesus' Incarnation and atoning action are "by the will of the Father and the work of the Holy Spirit."