Those who claim to be believers (but not all) have a tendency to impose divinity on something concrete like human,stones,wood,animals,etc
This is why we see concrete gods having definite shape,size and weight in different faiths.
Those who are atheists(probably agnostic people too) don't believe in God just because they don't see a concrete God.
It seems that , human beings are 'pulled' towards concreteness and are 'pushed' away from abstract.
Humans consist in the “heavy” body, mind, emotions and a more “spiritual” part.
I would unite in one amalgam material body mind and emotions (as, we can experience/see in every day life the effect of these last two).
While the “spitual” part, that is not seen, is often denied, neglected, ignored and misanderstood.
What I noticed is tha people often are clouded by physicity, mind and emotions that they can not perceive the deeper dimension that is inside them, so as you wrote, it seems “human beings are 'pulled' towards concreteness and are 'pushed' away from abstract”.
The exercise of reach our core/essence, leaving physicity, mind and emotions, can help to became aware of the “abstract”.