Many anthropologists believe that humans process the Divine in response to understanding the world in a series of opposites. Our concept of dark cannot exist without light, up without down, land without water, life without death, logical and illogical, etc. It is when there are in-betweens and idiosyncrasies that we become uncomfortable, and look for something other-worldly to explain this. I am not saying that this delegitimizes God or spirituality in any way. It is precisely the evolution of our human brain that allows us to experience what we perceive as the Divine consciously.
In Carses' book, he discusses how when we pit ideas against each other, one necessitates the other. Fundamentalists need progressives in order for their agenda to exist. The Pope needed Galileo, and vice versa. Christian believers need non-believers in order to fulfill the evangelical ideas presented in the Bible. The sacred needs the profane, to exist. The extraordinary needs the ordinary. Most things in our perception operate this way- or so we think. Can we perceive anything in between? We began with two genders and one sexual orientation, and now those are flexible. Our concept of race has been demolished by science and genetics. Things we once thought were concrete, are no longer. We are slowly learning that maybe dichotomies are not all there is to understand. After all, there are frequencies that we cannot hear- but they exist outside of our capacity to detect them.
Maybe spirituality is quite the same: there is more than we can perceive as humans, that's less clear cut than a "God beyond understanding." We have set up the dichotomy of an entity-God and the lack thereof. But what if the Divine is somewhere in between the two opposite ends of the spectrum- neither extreme, but somewhere inside- or even somewhere outside. The point is- what is there that we cannot know because of limited capacities, or our unwillingness to be in-between?