I have issues with the Messiah thing. I think spiritual interface by means of showing us how to connect to a deep God zone works better.
From an Abrahamic perspective:
The basic rule of thumb is we cannot transcend our nature.
Human nature is open to the infinite in every respect, but being 'open to' does not necessarily mean 'entitled to' nor 'able to' transcend itself. Grace, that is union with the Uncreate, is always an unmerited gift, and although the divine image is imprinted, as it were, in the depths of the soul, the soul itself is a created nature, and thus cannot assume the properties of the Uncreate under its own steam.
The 'Messiah thing', then, in Christian terms, is to identifiy Christ as the Logos of God.
God the Father is, in the words of the Fathers, the
narche anarchos – the Principle without Principle, whilst the Son is Logos or
arche, the principle.
To use your analogy (loosely) God the Father contains everything in the Divine Mind, and God the Son orders everything, according to the Father's will.
The stumbler is we then suppose terms like 'mind', 'will', etc. of the Father, when in fact the Father (and Son, and Spirit) are above all categories and forms. So these things – Mind, Will, Intellect, Understanding, Love, Justice, Mercy and so on, exist unformed and undifferentiated in the Divine.
An agent needed to save us is still an outside in approach instead of an inside out approach.
From a secular pov, yes. but from a spiritual pov, no.
Everything is Brahman, all natures are Buddha Nature, and in Christianity all natures are the individual and differentiated
logoi that flow from the undifferentiated
Logos. So it's not outside/inside for us, rather it's the idea of the (individual) self and Self-as-such.
To me, Mesiah is a tribal carryover of a sense of needing something out there to come in and save the tribe. Seems dualistic and pretty much just another version of idol worship.
OK, I can see how one can see it that way, but really that's not what the
sacra doctrina nor the tradition is pointing to.