Gandalf Vs. The Witch King

[Mugwump]

Toklien clearly said that LofR was NOT intended to reflect Christian theology in any way or to be analogous to any part of it, and the only similarities lie in those elements that exist in all religions and all world myth.

[Pitchwife]

Originally Posted by Dakêsîntrah

So, in some Gnostic theology, Jesus is not God, and the Trinity is not really a Trinity, rather manifestations of the Godhead Himself. Much like the Eldar who seemed to emanate from Eru. And of course, as Jesus was an emanation, he was also a created being who came to earth in the guise of a man, as a Messenger.

I can't claim to be an expert in Catholic, let alone Gnostic, theology, but I was raised a Catholic, and in the faith I was taught, there's a big difference between an emanation/manifestation and a created being - see the Nicene Creed, which stresses that Jesus was

God of God, light of light, true God of true God. Begotten not made, consubstantial to the Father

(emphasis mine).
I won't deny that Tolkien may have been aware of the Gnostic tradition - after all, he was a man of considerable erudition; but it's a far cry from there to assuming he endorsed its beliefs to such a point that he'd have modeled the metaphysics of Middle-earth on them. As you said yourself, Gnosticism was Roman Catholicism's ancient foe, and the Prof was a devout Catholic.

But we're straying a bit off-topic here. Back to the parallels between Jesus and Gandalf.

Originally Posted by Dakêsîntrah

The nature of both figures are more parallel than the events that surrounded them.

Quite the contrary, I'd say. Their nature was quite different - one an angelic spirit (that is, a created being, although of the highest order), the other the Godhead itself made flesh. What's parallel is precisely the events: both made the ultimate sacrifice by offering up their lives in order to overcome evil (although on vastly different scales, and as Zil observes it was rather incidental in Gandalf's case); and in both cases the Father/Authority accepted and vindicated their sacrifice by bringing them back from death in a form that still preserved their human nature (Christ's wounds could still be touched by Thomas, Gandalf still ate, drank and smoked), but was transfigured into something that death and evil couldn't touch in the same way as before.
Which is the point I was trying to make when I said earlier that you were doing your case no favour by stressing the parallels between them. Agreed, Jesus during his earthly life could be tempted by Satan and experienced fear of death to the point of sweating blood; but Christ Resurrected? Satan wouldn't have touched him with a long pole. And Gandalf the Grey might have had reason to fear the WK with his power newly boosted by Sauron, but Gandalf the White? Not with any shiny enchanted Sword of Hellish Flames in Middle-earth.
As for Olórin (or the Eldar, for that matter) being an emanation of Eru himself, I'm really curious what in all of Tolkien's works (apart from Sumerian mythology, which he may or may not have been familiar with) you base this on.

By the way, thanks for adding some intellectual challenge to this discussion of a rather embarassing movie scene. This is fun!