Another thing that should go without saying: whatever your Christology is (your beliefs about who Jesus Christ is, how he is related to God the Father, how he is related to mankind, what he has done, etc.) determines what your soteriology is (the teachings about what 'salvation' is).
I've been reading, in fits and starts, through R.P.C Hanson's "The Search for the Christian Doctrine of God" about the early 4th century Arian controversy. One of the problems he brings up, as he is detailing the history of interpretation, is that often scholars have assumed that Arius had no soteriology, that is, he was concerned only with the oddly impenetrable philosophical dogmas concerning the immutable, Platonic/Aristotelian High God (the Father) and the lesser, "second," mutable god (the Son). However, looking at the Patristic preoccupation with the "economy of salvation" (how God is working to save His creation in time -- often translated, interestingly enough, by the word Incarnation), it is hard to believe that Arius and the Arians could have made a sufficient splash into the turbulent theological waters of the time without a rival soteriology -- a rival economy to the pro-Nicenes.
I won't go into details of what that rival economy is, Hanson does a much better job than I could. The main point that I want to explore is: what soteriology does classical Christianity, that is, Christianity bounded by the creeds, produce? The Creeds, as is well known, are concerned either with the relation between Father and Son (Nicene, for example) or the relation between the Divine Person of the Word/Son and the assumed human nature in the history of Jesus the Messiah (Chalcedon, for example). That these are implicitly soteriology is not always obvious to those of us who aren't Eastern Orthodox, but they are. For the Trinitarian creeds (the first category), the assumption is that only God can save us, Jesus Christ saves us, therefore Jesus Christ must be God. The form this takes is the (seemingly still) controversial homoousias -- Jesus, the Word/Son, is of the same substance as the Father (the East would take this in a different -- and I think better -- direction than the West: God the Father is the Monarch from whom the Son and Spirit are respectively generated and spirated, instead of a (seemingly) autonomous and impersonal substance in which all three are implicated). The Christological creeds, then, take this soteriology further: certainly only God can save us, but mankind (humanity as such) must be brought by this action from death to life, so the Son must assume a full human nature (complete with body and soul: will included) that is brought through death to life, both in the fact that God has assumed it (the effects of the Divine Person of the Word on the body in the Incarnation) and the cross/resurrection event. If this does not happen, then we cannot be saved in the fullest sense: we cannot have a real union with Christ through the Spirit, who is the Life of God Himself (it is important here to remember that Patristic theologians never forgot that spirit can also mean "breath," that is, the very principle of life in an animate being: God's Spirit is His Life which He shares with us who are joined to Christ through faith and baptism.
This means that the concept of 'salvation' needs to be carefully explained. Certainly there is not an emphasis on salvation as a one-time event/experience of being "born again," as we find in modern evangelicalism broadly. Instead, the one event of salvation is that of the Incarnation (broadly conceived to include everything from the "incarnation proper" -- the miraculous conception of the Lord -- to his death, resurrection, ascension, and Session at the right hand of the Father) that, as both a historical, time-bounded reality and as the eternal reality of God as Trinity (see my post The Reality of Worship on this) is much broader and inclusive and objective than a subjective "born again" experience. 'Salvation,' as far as the human believer is concerned, entails being brought into the worshipping community of God (this is the real import of justification), and being conformed to the image of the Son progressively (sanctification or theosis). It is, then, a "once for all" event that reverberates throughout every moment of creational history: 'salvation' must be both entrance into the Church and growth into sainthood.
The creeds, by and large, assume the first aspect of salvation: Jesus Christ has come, he has died, he has risen, he will come again. The second aspect, the theotic aspect, is what they are concerned to safeguard. Our union with Christ, the progressive submission of our wills to the will of God (hence why monothelitism was such a threat!), must be maintained. If Christ is to not only be our Savior, but our model ("walk as he walked" as John says), then his humanity must be full and we must be conformed to that humanity. The 'how' of that I've attempted to explain in my Real Predestination series: the Spirit works in us and we work with the Spirit (asceticism and God's work are closely united). So man, by both the work and the hypostatic union of Christ, is brought to conformity with the Son in his glorified, resurrected humanity which must, if it is to overcome death and corruption, be united to God Himself through the indwelling of the Spirit.
The Reformed tradition, for the most part, does not make much of theosis. However, if we are to call ourselves orthodox, we must wrestle with the implications of the creeds we claim to profess. Part of the reason, it seems to me, that Calvin and his successors are often accused of Nestorianism is because we have not, by and large, connected our Christology to our soteriology.