THIS gets to the point! There are all sorts of terms that could be thrown around, but Salvation in the pure sense doesn't happen until after the Day of Judgment, while EL starts before, immediately upon belief, ready or not. This should clarify at least a little, but I wouldn't go making a doctrine out of the phrase Salvation is a result of EL.
Salvation as related to EL seems more general instead of nitpicking.
How is it that a practicing Buddhist doesn't see the ego problems this statement comes form? But you are most certainly right, this is one way G-d keeps His Power from being misused by the impure.
2 things: 1) I never considered myself a practicing Buddhist, since in a strict sense, I'd be in a freaking monastery or otherwise being very hermit like, growing my own food and stuff, but I'm not. And 2) This seems to be a misunderstanding of Buddhist ideas about self. They don't deny that we have a self in the empirical sense; we experience it, that' s undeniable. Buddhists only deny that this is something you possess and carry with you after death in some sense like a soul, though the term atman in Hinduism where the term anatta (see my thread in Christianity and World Religion if you want more discussion on that) comes from.
And this doesn't seem like God keeping its power safe from the impure, but simply keeping its power only for the elect, to use another theological term you might be familiar with.
I guess you skipped over the part where I said I don't think that was given as biology text, but instead has Spiritual applications, directly relevant to what we're discussing?
All of this seems to think we all have a God shaped hole as people put it, which I don't believe is the case. Correct me if I'm wrong, as usual, it appears.
Enter a new phrase: "co-laborers together with G-d." Do you see how this resolves your perceived dilemma? Back to defining EL, within C?
Not really, it only seems to raise us to a level that can give us an unjustified sense of entitlement, not unlike the problematic idea from Genesis that we're supposed to subdue the earth.
Ah, you
do get back to it.

It's not a question of arguing over what it means, or what it is or isn't. If you're going to ask why it's desirable, you have to know what is meant by "it." And since you're only engaging C's in EC, and since "it" is apparently rather distinct in our respective belief systems, then it is not wise to go mixing and matching.
With enough understanding of what EL is within C, you may be able to find something within the Eastern systems that parallels. If you do, I'd certainly be interested to find out. Too bad Tariki isn't posting in this thread. Could you call his attention to it via PM? It's seems we might be ready to settle down to a reasonable focus.
You're not making it clear what it is, but I also don't think there's a direct parallel that exists in Eastern systems, apart from possibly Sikhism, though even that's questionable, since it might be considered a fusion of monotheism from Islamic influences and mysticism derived from Hinduism.
Your first problem seems to be communicating this in a way that I can understand. If you think I understand the way you communicate it from your perspective, then you seem to already miss the point.
The problem with saying that there is some version of "It", or Eternal Life in my belief system, is that this is more derived from general explanations I've gotten from other theists in the general sense. It's not like I ever really believed in that myself, but merely that I had concepts of it to draw from in a sort of database, you might say.
This gets further complicated because RC terminology is different from basically everybody else, and I have no idea if your ideas re: C come from RC or where. Your thread "incomprehensibility of theological language" comes to mind, where you concluded that any given term is only meaningful in the context of one individual's use of it, or in dialog if it's defined clearly enough.
Obviously that's true
RC terminology is different because they seem to make the biggest effort to sound like philosophers instead of strictly theologians. I might disagree with Aquinas, but his arguments are systematic and pretty detailed in their support for the premises and inferences he makes, with sparse references to scripture, since he didn't think people were going to be convinced by scriptural apologetics, but first and foremost by logical arguments.
So if what I said about theological language is true, why do you insist on not trying to make a general explication of your contextual language for outsiders?
So while I understand the notion in your title that EL and immortality are interchangeable, I'm saying that doesn't really pertain to C. So in what ways are they different?
Interchangeable is the wrong word; they're related. You can be one or the other separate from the complementary term. You can be eternally living without being immortal; ala elves from LOTR; you can be immortal without being eternally living, ala, reincarnation where you retain all memories of your previous lives and continune to be reborn every time you die with your memories continuing to pile up or perhaps just being resurrected and rejuvenated every time you die by trauma or old age, which would be equally unpleasant in that you'd have to be reconstructed every time so to speak; and you can be both eternally living and immortal in a different sense, such as being indestructible and also maintaining an ideal state of living, like being eternally youthful.
1) We can't truly comprehend immortality.
Comprehension and construction of something from divine revelation aren't identical. Aquinas can attempt to construct ideas about God, such as hypostasis and the like, as they had been explained through history, but this isn't the same as him comprehending God itself. Do you think I don't understand the difference in a religious context? I can imagine what immortality could be like, but I can't comprehend it, because of the obvious fact that we have not observed it in any conclusive sense.
2) We are temporal, and understand "now." We can make habits of living in the past, or the future, but even then the scope is not even a blip compared to immortality, in reference to which time becomes meaningless.
We don't understand just now. We can understand the past through history and we can understand the future through predictions and, in your case, prophecies. Am I wrong? Or are you implying a different idea of understanding, like Augustine saying that the present is the only thing that really exists in terms of time, since the past is always gone and the future doesn't yet exist?]
And your last phrase there about time becoming meaningless is relevant to the discussion about why immortality or eternal life would be desirable or undesirable.
3) There ARE elements of Life that are not temporal in the least, but are "fixed," to borrow a word you used earlier. This is not something C's reach out for or wish for as you suggested, but a reality we are forced to reckon with. Trying to describe the specific elements is not what's important here, yet. Dealing with this reality may be simply one way of referring to Christian maturity.
Consistency is different from fixity. There are dynamics to the laws of biology, chemistry and physics, but they are nonetheless consistent according to scientific observation. Dealing with reality can be done in different ways and not all of them are mature, even if you are apparently an adult. Just a thought.
4) Learning to recognize these elements and relying on them, may be a very workable way of speaking about "entering into Eternal Life." I'm trying to pick nits with my words, and can't. I trust you'll help?
In the Christian context, sure, I could begin to understand this. But even if I understood it, it seems to run into a wall when we try to talk about why it would be desirable. I can understand many things, but I neither have to assent to their reality or consider them relevant in my life until things demonstrate otherwise; e.g. if a pixie proves itself to not be a dream or hallucination and then shows that pixies do exist. but until then, i can merely believe, like I do about God, that pixies are something believed by others to be real, but nothing further in my own beliefs.
So you see I am not talking about waiting to die, for the sweet bye and bye, speculative sort of thing. EL is a possession of C's, here and now, that we are to KNOW we have. Another way of saying it that might make more sense to you is rather than our own nature which is defined by G-d as degenerate, we can partake of a new Nature which is regenerated, and being regenerated.
But the sweet bye and bye was so prominent in the hymns. But supposedly Presbyterians are predestination sort of people, so even if I was a Christian today, I'd probably be the worst kind of heretic in their eyes.
So EL is a new quality you acquire, it sounds like, in that it's like a lizard losing an arm, but growing it back. And theoretically, the new arm is better.