That's because you're dealing with abstractions, something the human brain has evolved to use widely. If you've ever seen an infant in the arms of its carer, you'll very usually see the carer instinctively speaking motherese, and the infant looking at the carer's face, and where the carer points, and imitating what the carer says when pointing ─ "car", "plane", "doggy" ─ with the result that the infant learns from all these "doggy" examples the abstraction "dogness", the ability to identify a dog it hasn't seen before.
"Justice" is based on the human judgment "just" and arises from our evolved like of fairness. Someone deals with someone in a manner the observer thinks is fair, proper, just, and from this example of "justness" we get the abstraction "justice".
We get the abstraction "love" in an analogous way, from examples we judge to be loving.
Our mathematical objects ─ numbers, lines, planes, e, π &c ─ are equally abstractions. You can't count, for example, until you, the observer, have made a judgment: what do I want to count, in what field do I want to count it? How many billiard balls in Chicago? How many hens in the barn?
And that's also why you never see uninstantiated love, justice or 2s running around in the wild. They're all abstractions from instances we judge to be loving, just, paired, and so on.
"God" (as a "person") is not an abstraction but a concept without a real counterpart ─ you can't point out God in the real world, because God is only found in individual brains.
And in every brain God is different, just as all the gods in all the cultures of the world are different, just as the Christian God can be triune or not, require an intermediary Jesus or not, keep Sunday rather than Saturday holy or not, and so on through the thousands of Christian sects.