In integral theory there are three faces to God or the divine experience.
1) personal - recognizing the divine within - your higher self or the ultimate self-consciousness within you.
2) interpersonal - an "I/you" relationship to the divine. Seeing the divine as an exterior being 'other' than you. This creates a relationship to the divine very different from 1)
3) objective - the divine is in all things, it is out there, it is the context of existence...
Religion often only concerns itself with one or maximally two of these facets of experiencing the ineffable or engaging in what we perceive as a deeper order that is not directly apparent but is in some way related to consciousness.
This is in response to SWIMfriend's comment about 'theo' necessarily relating to an entity. That would be 2) in the integral theory approach. But the broader scope of the spiritual experience can still contain the divine without focusing solely on this 2) aspect of it. Personally I enjoy all three facets and I find 2) very helpful and inspiring at times. But I've made my peace with all these connotations that used to evoke in me gag reflexes and stomach cramps. I can use the terms God, spirituality and enlightenment with a clear conscience these days because I have a clear idea of what they mean to me personally, which is free from historical traumas in the collective consciousness that usually seem to be linked to these words and make them so hard for us to stomach. The idea of considering the cosmos to be a supreme being, a kind of super personality does not bother me, because I see it as just one way of looking at it. One of three, or one of an uncountable myriad.
I think for me the noteworthy thing to say is that we are talking about something we experience, something that is real primarily only through our experience. This means that communicating this will always be more difficult than giving simply objective information about say 'how to put together a piece of furniture'. On the other hand considering that we all share common structures, it would follow that we all share common abilities to experience certain things. Mystical experiences are one of these things and thus I think it is valuable to establish communication about these 'realities' or these experiences.
I don't see the point in arguing about what Christians do or don't do with their scriptures. Our individual explorations of consciousness seem to pose these questions regardless of confession, once one delves deep enough, and provides these experiences as well. What is the deeper order, why are we here and where are we going? What is the self, this existence, what is consciousness and where does it end/begin?
Expanding beyond the body during high doses of psychedelics, communicating with omniscient entities, connecting to the cosmic process, feeling your self flood with sublime energy... We can just as well use different words for them and speak of God here; it doesn't matter as long as we understand that we are speaking of experiences rather than abstract concepts. Because then I think this word really does have meaning, and not just something arbitrary, but something that is accessible by all humans IMO.