Anderson Brown has an interesting post arguing that agnosticism is not a theological position because it is the claim that one cannot make a metaphysical assertion about the existence or non-existence of God and, therein rejects both the possible alternative theological positions (that there is a God and that there is not one):
A “theological position” would be an opinion of some sort (that’s the “position” part) about something (say, existence or lack thereof) specifically about God (that’s the “theological” part). “Either God exists, or God does not exist” is a theological position, because it contains the premise that both sides of the disjunction make sense. Put in metaphysical terms: that it’s possible that God exists, and possible that God does not. But I’m not sure the agnostic is entitled to that much.
But Brown does not think that the agnostic is entitled to his position that the question of God is in principle unknowable since there are available reasons for and against the proposition that there is a God even though one might not be convinced that they conclusively lead to one conclusion over the other. Agnosticism is not therefore a theological position but a refusal to do theology. Brown claims he is himself, therefore, a sceptic since he thinks there are reasons to believe and not to believe and yet is unsure which way to go. And he rejects agnosticism as an alternative altogether (except as the alternative to evade the questions altogether), again because there are possible reasons that can be weighed, so the question is not simply beyond answering rationally.
For my part, I’m not sure that questions of atheism, theism, agnosticism, skepticism, pantheism, etc. as Brown lays them out are really “theological” positions but rather, simply philosophical ones. As long as we are on the plane of discussing God as a plausible or implausible, theoretically knowable or theoretically unknowable, theoretically proven, or skeptically doubted being, I think we are still doing philosophy.
It’s only when we are accepting a faith tradition (or multiple ones) and taking into account its sources, and not restricting ourselves only to rational ones, that I think we enter into doing “theology” proper. This is because theology is the study of God or gods and assumes there is a God or gods from the outset. So, I would argue that atheism, the philosophical position that there are no gods available to study, is a rejection of theology as much as agnosticism is.
And skepticism is a choice to hold off on doing theology until there is philosophical evidence that would permit acceptance of (a) a metaphysical entity known as God and (b) the authority of a specific faith tradition or traditions for interpreting that God’s nature/works/etc., in the terms of which one could then proceed to do “theology.”
Now, maybe you’re equally as open-minded a skeptic about special revelation, capable of persuasion to accept it as you are of the metaphysical God, in which case you are a skeptic about the existence of God and a skeptic about whether theology contains any truth at all. But that’s something specifically different than simple skepticism about the philosopher’s God that gets combined with confident atheism about the specially revealing gods of faith.
Personally, I am simply a metaphysical skeptic when it comes to the existence of a unified, eternally existent “ground of all being” or Anselmian “perfect being” of some sort. But based on my views of epistemic justification, in principle I completely rule out special, narrowly given, revelation as a legitimate source of authority and so am atheistic with respect to all religious interpretations of God the second they go beyond the philosophically plausible.
I do not believe there is any such field of knowledge called “theology” (except if by that term you mean a species of literature, myth, and history of ideas.) And technically it is possible (since anything is possible) that some theological tradition is actually true but we can in principle have no justified knowledge of it and so should never make belief claims about it, even if it were to actually be true. There is a difference between something’s being true and it’s being rationally affirmable. Special revelation, rejecting the standards of public reason, is in principle not rationally affirmable and so even were it to contain truths (which is extraordinarily unlikely anyway), we would still be unjustified in believing them.
To that extent that mere possibility of special revelation remains, I might really best be called an agnostic about whether there can be special revelation since I think we can never know whether it does or does not happen since it is in principle not subject to rational corroboration or assessment. But, being committed to the principle that we should not affirm what we cannot have adequate reasons to believe, that means rejecting the claim that the theology done from within that “special revelation” could ever be called “knowledge.” Even if it happened to be right.