A difficulty with theological dogma (whether about god or about 'reality') is its insistence on metaphysical literality. Dogmatic truth cannot just be 'a way of speaking', however carefully we qualify that phrase.
There is an important sense in which science can be comfortable with 'We can talk as though X is true' and 'X is true' being methodologically indistinguishable, when understood in the most unrestricted way. Dogma cannot.
This has some odd consequences. One is that religious 'truth' trumps intelligibility - so that we end up with 'mysteries' like the Catholic trinity. Another, related to this, is that it must be possible to distinguish meaning from truth-value - since specifying a theory of truth ('X is true iff Y') implies a methodological test (in the broadest sense of a 'specific way of finding out') that at least implies a difference in meaning, even if meaning can't be entirely reduced to methodology. 'God exists' and 'we can talk, in the most unrestricted way, as though God exists' must mean different things, even though the methods used to test the truth of the first are exactly the same as the methods used to test the truth of the second.
One place that we could look for such a difference might be in subjective experience which, as David Hume observed, commands conviction without providing arguments. No methodological test can be specified. Willard Quine went with this in the end, by more or less stipulating that sensory input just was the basis of scientific proof - a perspective as dogmatic as any credo.
From a psychological perspective, the experience of conviction without awareness has its place in what is called 'procedural knowledge' - we can know how to do something without being able to explain how to do it or even being able to properly articulate our knowledge; frequently without even being able to give a very satisfactory account of how we came by this knowledge. Facility with language depends upon extensive procedural knowledge - most people have far more semantic and grammatical knowledge than they can articulate or give an account of. The 'obviousness' of how to talk, to most language users, makes the link between the inner world of 'experience' and the shared world we describe to one another. Our congruent public narrative convinces us of the congruence of our sensory apparatus. Without any 'argument' ...
If we attempt to construct a more public test based on this ('let me show you and you will agree with me'), we render important truths vulnerable to empathic failure unless we are ready to resort to accusations of bad faith. If say that I do not see your god from the best perspective you can construct, then either your test has failed or I am a liar.
'We agree about how to talk', however, must be true, to some minimal extent, before we can put together narratives about 'procedural knowledge', or ask questions about 'reality', or construct advantageous perspectives. This is a matter of intelligibility rather than visceral conviction (although it may be this as well) and so doesn't solve the 'really' problem in the kind of way that would relieve any felt metaphysical anxiety. If the existence of God could be derived from the possibility of intelligible speech, the 'as if' problem would go away, but would make the existence of God a consequence of our ability to talk to one another. I'm not sure how satisfactory this would be to a dogmatic believer.
The same thing applies to the relationship between the experience of being here and the value of the noun 'I'. While solipsism may be grammatically unintelligible, the 'fact' that we directly experience only one 'sensorium', and the 'fact' of our limited ability to share it, point in the other direction - which means no more nor less than that the 'unshareable' parts are outside the scope of intelligible discourse. The experience of 'I' and our knowledge of 'God' seem to belong in the same sensory wilderness.
It is much harder to dispense with 'I' than with 'God' in first-person conversations of course. And substituting 'God' into sentence functions doesn't generate Moorean paradoxes. Which, I suppose, is a kind of demonstration of agnosticism without relativism. "I don't need 'God'" makes sense, but "I don't need 'I'" doesn't.
A person as viscerally convinced of the existence of God as they are of the existence of the objects in the room they are in may find it difficult to hold a conversation with someone who does not share one or the other of these convictions. Whether it is a 'matter of fact' that the objects, or God, are 'really' in the room will not be relevant to their difficulty. If the difficulty is insurmountable, it won't even be clear what they might mean by a 'matter of fact'.
When Richard Dawkins asked Robert Winston, a practising Jew, how he, a 'man of science' could believe in God, Winston said "I'm going to give you a very Jewish answer: It depends on what you mean by 'God'".
He understood some important aspects of the relationship between methodology and meaning. As he might.
