Christ
Early in worship after Paul, Jesus is the Christ, the Lord's anointed, the Messiah and the Redeemer. Ebionites said he was only human; Docetists said he was only divine. Christians said Christ both fully human and fully divine. The Alexandrine and Antiochene schools could not agree and the Western Church, much more concerned with pastoral than philosophical issues, gained prestige by being even-handed and mediating the crisis
The Alexandrine position based on the work of the founder of Neoplatonism, Plotinus (205-270), was that Jesus was divine, possessing the attributes but not the limitations of humanity (unitive). Antiochene position, based on close proximity to Galilee and human witness, focused on the Jesus of history; it accepted divinity but held that the two aspects did not interfere with each other (disjunctive). In the West Tertullian had posited two natures in one substance, revived by Augustine.
In the Fifth Century the controversy reached its height. Nestorius of Antioch (386-451) proposed two natures and two persons; and Cyril of Alexandria (376-444) said that the union in Christ must be more than 'moral' being only one subject; what must be said of him must be said of him as a single person. At the Council of Chalcedon (451) the issue was settled by Pope Leo the Great (r 440-461):
Synthesis: Christ is one person with two natures. This does not explain the incarnation but it clarifies that Jesus is: like us except for sin; divine; one person.
In the 19th Century, reacting to the enlightenment (and fundamental to German liberalism - KC) there began "the quest for the historical Jesus) which in turn triggered a reaction from Barth and Bonhoeffer (1906-1945).
Christianity was never divided on the concept that Jesus was saviour but the debate on how began in the 12th century with Anselm of Canterbury's (1033-1109) book Cur Deus Homo: 1. If all we have we already owe to God, how can we repay? 2. Worse, the slightest sin is an infinite offence. 3. Only God can repay God; but 4. Not fitting for God to repay a human debt; so 5. Jesus was 'sent' to repay God (the juridical or substitutional theory of atonement).
Peter Abelard (1079-1142) countered that Jesus was an example of unforgettable love so that we no longer hide from wrath (subjective or moral theory of atonement). This was dismissed, significantly, by Bernard of Clairvaux (1090-1153) as Pelagian.
A third view, that Christ conquers evil and that this connects Incarnation and Resurrection, emerged in worship: in the 4th Century, the Eucharist is Resurrection; but in the 'dark ages' the focus was on penitence and the Cross and Jesus moving from victor to victim. Anselm 'won' right up to the Council of Trent (1545-1563) and Protestantism followed him such that the substitutional theory of atonement became a test of doctrinal orthodoxy among American 'fundamentalists'. However, there was a 20th Century revival of the concept of Christ as victory over Evil.
Synthesis: There has never been agreement on theories of atonement; but the love of Jesus should be emphasised more than the "wrath of God"; and the Cross is inseparable from the Resurrection.