Do you ever doubt your atheism?

[The Grand Nudger]

Well, I don't know if I'd quite agree. That we can reason negatively to what this thing cannot be, if our logic is at all to be trusted, and hence come up with ideas such as "necessary," "infinite," "intelligible," that cannot be said to equal comprehension.

It can't? Starting to sound like a god of semantics, eh? Comprehension has a few meanings, I'll grant you that:

the act or action of grasping with the intellect
knowledge gained by comprehending
the capacity for understanding fully
http://www.merriam-webster.com/dictionary/comprehension

-You appear to be angling for the third, but in that case the qualifier "infinitely" becomes redundant. I'm satisfied with the others, and your list of attributes and the process that you have leveraged to generate those attributes appears to be squarely within the remit of those definitions. I -did- suggest using a different word....lol.

I say "infinitely incomprehensible" because everything that is confined to empirical experience, and finite, as all else that is not this thing

What thing? The thing that is not all of the other things? That pretty much describes -any- thing. I'm just ribbing you here, I understand what you mean..lol.

would seem to require, could never have any amount of knowledge that would enable an empirical conception of this thing--as it is only rationally defined, and as it is the prerequisite for any empirical experience in the first place.

Ah, but I don't think anything that could be said to be the ultimate "necessary thing" would fit that bill (as empirical experience is a ways further up, one would imagine). You've also seem to have declared here that we would never be able to determine whether any claim about this "x" is sound - reducing the position, and such claims (in my estimation) to uselessness. As you seem to be alluding to below

Can rational without empirical be conceived as anything, besides a glimmer of the idea only? I don't know, but I don't think so.

Not if we insist that what is valid -must also be sound- in order to lead to truth. We're pretty well aware that our imaginations aren't limited in -all- of the ways that our universe is. We're capable of coming up with empty sets and hollow ideas. But if your bar is that low for god, then go ahead and claim your god? I'm just going to call it imaginary (but you already knew that...lol). I think that the whole god thing just fizzled out like soda though.....right at that point.