In western Christian theology, atonement describes how human beings can be reconciled to God. Atonement refers to the forgiving or pardoning of original sin in particular, and sin in general through the death and resurrection of divine Jesus, made possible in the reconciliation between God and his creation. Within Christianity there are, historically, three or four main theories for how such atonement might work: Ransom theory/Christus Victor (which are different, but generally considered together as Patristic or “classical”, to use Gustaf Aulen’s nomenclature, theories, it being argued that these were the traditional understandings of the early Church Fathers); Moral influence theory, which Aulen considered to be developed by Peter Abelard (called by him the “idealistic” view); Satisfaction theory developed by Anselm of Canterbury (called by Aulen the “scholastic” view); The penal substitution theory (which is a refinement of the Anselmian satisfaction theory developed by the Protestant Reformers, especially John Calvin, and is often treated together with the satisfaction view, giving rise to the “four main types” of atonement theories – classical or patristic, scholastic, and idealistic – spoken of by Aulen). Other theories include recapitulation theory, the “shared atonement” theory and scapegoat theory. The English word ‘atonement’ originally meant “at-one-ment”, i.e. being “at one”, in harmony, with someone. It is used to describe the saving work that God did through Christ to reconcile the world to himself, and also of the state of a person having been reconciled to God. Throughout the centuries, Christians have used different metaphors and given differing explanations of the atonement to express how the atonement might work. Churches and denominations may vary in which metaphor or explanation they consider most accurately fits into their theological perspective; however all Christians emphasize that Jesus is the Saviour of the world and through his death the sins of humanity have been forgiven. The four most well known theories are briefly described below: One of the earliest explanations for how the atonement works is nowadays often called the moral influence theory. In this view the core of Christianity is positive moral change, and the purpose of everything the Jewish Jesus did was to lead humans toward that moral change. He is understood to have accomplished this variously through his teachings, example, founding of the Church, and the inspiring power of his martyrdom and resurrection. This view was universally taught by the Church Fathers in the 2nd and 3rd centuries AD, along with what is called by Aulen the classical or patristic view, which can be variously interpreted as Ransom or Recapitulation, or under the general heading of “Christus Victor”. The moral influence theory also enjoyed popularity during the Middle Ages and is most often associated in that period with Peter Abelard. Since the Reformation it has been advocated by modern philosophers like Immanuel Kant, and many theologians such as Hastings Rashdall and Paul Tillich. It remains the most popular view of atonement among theologically liberal Christians. It also forms the basis for René Girard’s “mimetic desire” theory (not to be confused with meme theory). It would be a mistake, however, to read this theory, or any of the theories, in isolation from the others. The second explanation, first clearly enunciated by Irenaeus, is the “ransom” or “Christus Victor” theory. “Christus victor” and “ransom” are slightly different from each other: in the ransom metaphor Jesus liberates humanity from slavery to sin and Satan and thus death by giving his own life as a ransom sacrifice (Matthew 20:28). Victory over Satan consists of swapping the life of the perfect (Jesus), for the lives of the imperfect (humans). The “Christus Victor” theory sees Jesus not used as a ransom but rather defeating Satan in a spiritual battle and thus freeing enslaved humanity by defeating the captor. This theory ‘continued for a thousand years to influence Christian theology, until it was finally shifted and discarded by Anselm’. The third metaphor, used by the 11th century theologian Anselm, is called the “satisfaction” theory. In this picture humanity owes a debt not to Satan, but to the sovereign God himself. A sovereign may well be able to forgive an insult or an injury in his private capacity, but because he is a sovereign he cannot if the state has been dishonoured. Anselm argued that the insult given to God is so great that only a perfect sacrifice could satisfy, and that Jesus, being both God and man, was this perfect sacrifice. Therefore, the doctrine would be that Jesus gave himself as a “ransom for many”, to God the Father himself. The next explanation, which was a development by the Reformers of Anselm’s satisfaction theory, is the commonly held Protestant “penal substitution theory,” which, instead of considering sin as an affront to God’s honour, sees sin as the breaking of God’s moral law. Placing a particular emphasis on (the wages of sin is death), penal substitution sees sinful man as being subject to God’s wrath with the essence of Jesus’ saving work being his substitution in the sinner’s place, bearing the curse in the place of man (). A variation that also falls within this metaphor is Hugo Grotius’ “governmental theory”, which sees Jesus receiving a punishment as a public example of the lengths to which God will go to uphold the moral order.