Not poor as in impoverished, but poor as in not very good.
One can spot a poor writer easily: they tell you what a character is.
A good writer is not like that. A good writer will show you what a character is, by what he or she says and does, and their effect on other characters. Show, not tell.
God in his relationship with Israel and indeed the rest of us is a 'good writer'.
He shows us who he is and what he is by his actions, but what he does. He doesn't just tell us to worship him because he is God; he tells us that it is because he is our creator (points to Genesis 1-3). He tells Israel to worship him because he is their rescuer in real historical actions; exodus from Egypt, preservation at the Red Sea, sustainment in the wilderness.
This is God at work in the real world; not a mystery god who has to tell us to do things with no real world salience: the pagan gods, the gods of myth, the dream-time gods.