– atonement The Apostolic Fathers, discussed the death and resurrection of Jesus, including Ignatius (50–115), Polycarp (69–155), and Justin Martyr (100–165). The understanding of the Greek Fathers of the death and resurrection of Jesus as an atonement is the "classic paradigm" of the Church Fathers, who developed the themes found in the New Testament. During the first millennium AD, the ransom theory of atonement was the dominant metaphor, both in eastern and western Christianity, until it was replaced in the west by Anselmus's satisfaction theory of atonement. The ransom theory of atonement says that Christ liberated humanity from slavery to sin and Satan, and thus death, by giving his own life as a ransom sacrifice to Satan, swapping the life of the perfect (Jesus), for the lives of the imperfect (humans). It entails the idea that God deceived the devil, and that Satan, or death, had "legitimate rights" over sinful souls in the afterlife, due to the fall of man and inherited sin. The ransom theory was first clearly enunciated by Irenaeus (c. 130–c. 202), who was an outspoken critic of Gnosticism, but borrowed ideas from their dualistic worldview. In this worldview, humankind is under the power of the Demiurg, a lesser God who has created the world. Yet, humans have a spark of the true divine nature within them, which can be liberated by gnosis (knowledge) of this divine spark. This knowledge is revealed by the Logos, "the very mind of the supreme God," who entered the world in the person of Jesus. Nevertheless, the Logos could not simply undo the power of the Demiurg, and had to hide his real identity, appearing as a physical form, thereby misleading the Demiurg, and liberating humankind. In Irenaeus' writings, the Demiurge is replaced by the devil, while Justin Martyr had already equated Jesus and the Logos. Origen (184–253) introduced the idea that the devil held legitimate rights over humans, who were bought free by the blood of Christ. He also introduced the notion that the devil was deceived in thinking that he could master the human soul. Late Antiquity and early Middle Ages Following the conversion of Constantine and the Edict of Milan in 313, the ecumenical councils of the 4th, 5th and 6th centuries, that focused on Christology, helped shape the Christian understanding of the redemptive nature of resurrection, and influenced both the development of its iconography, and its use