Yes, it's more like an abstract concept. It doesn't exist in the same way that an individual exists, but an individual is capable of embodying the concept. It's much the same as a physical object cannot literally become the predicate called 'blueness,' it can only possess that concept or predicate as part of its being. Although, in the case of being the 'universal man,' it doesn't comprise just a part of the individual's being, but rather, it constitutes its entirety.
Ibn Arabi
Wasn't Ibn Arabi the guy that said, 'there is nothing under my cloak that is not Allah' and was subsequently and quite rightly lynched by a mob of raging beardos? In any case, I understand what he says about being just a 'mirror,' and that this state bears some semblance to the nature of God.
I think I actually remember the Tailor stating at some point, or maybe I read it elsewhere, that the 'baatin,' linguistically means 'empty, void, null.' I guess this 'nothingness' is the default nature or attribute of God; 'laysa kamithlihi shay''; 'there is nothing like him.' I take this quite literally, and I understand it to be that God does not resemble any predicate or object. Hence, its nature is nothingness.
But anyway, if one becomes like nothing, as in the ascetic who attains moksha, or the bodhisattva who attains nirvana, then one immediately reaches a state like that of God's own nature. When a person does not identify one's own self (if such a person retained a sense of self at all) as being anything, neither man nor animal, neither rock nor tree, then one merely becomes a mirror that is aware of everything else, yet does not associate itself with any emotion, body, individual, identity, etc.