Jesus being fully divine and fully human is a mystery and certainly one valuable for us to take in contemplation. Here's the portion of your post that struck me:
Christ lived a sinless life and we certainly imitate him in every way that we can, but of course he was God, so he had a bit of an advantage in following the command "be ye perfect"! Certainly he was tempted in all ways as we are, and his human nature was like ours in all ways except for sin -- his was a "pre-fall" human nature, unlike ours.On first reading the initial portion seemed in contradiction to what followed.
When I contemplate the sorrowful mysteries, for example, it is me in the place of Christ being tortured and shamed.. sharing this in human nature in compassion with Jesus. If He had "a bit of an advantage" here, then..?
But I don't think this is what you refered to in "be ye perfect" though I think it can't be separated?
Secondly, I'm not familiar with the difference in Jesus's human nature and ours vis a vis "pre/post-fall."
As far as our human nature, don't we both start at the same place, if we are baptised? Doesn't this place us both at pre-fall?
Mostly, this, to me is a key focus of contemplation of the mystery of the Incarnation and I benefit from others discussion of it. If you have time for further comment, thank you..
Orthodox patristic teaching is that Christ assumed human nature as it was before the fall. He submitted voluntarily to the "unblameworthy passions" (hunger, thirst, weariness...). The fact that he did not assume fallen human nature does not take away from his likeness to us, for sin is not a part of human nature as God first created it, but is rather something parasitic. So Christ having an unfallen human nature does not compromise our salvation. One would include in this the suffering he endured -- his submitting to suffering and being killed was not sinful (although the Gnostics had other ideas.)
My point was that Christ was fully God and fully man. His sinless life, his death and resurrection were to achieve our salvation -- not his own. It was not so he could conquer death for himself, but for us.
The Theotokos was a human being who was born with the effects of the ancestral sin -- Christ was not. She labored for her own salvation, which she needed -- Christ labored for ours, and didn't need salvation.
The Theotokos is the exemplary Christian -- Christ is not a Christian, he is the Christ.
By taking the Theotokos and putting her into a special category where she was conceived differently from the rest of us, this makes her more than human, but less than God -- precisely what Protestants accuse those of us who revere her of doing.
If our baptism put us in a pre-fall state, then we would not get sick or die unless we sinned. Since infants who have been baptized but haven't yet sinned get sick and die, it is clear that baptism does not put us into a pre-fall state.