Comparing God to man is a legitimate analogy in a certain sense.
This argument is used in the debate Does God exist?.
This argument is an objection to A God in the image of man is too human to be credible.
Summary
Quotes
“Hume argues that if we use the analogy with a human agent, we'll have to go all the way and postulate that the god who gives order to the Universe is like men in many other respects. "Why not become a perfect antropomorphite? Why not assert that the Divinity or divinities are corporeal, that they have eyes, a nose, a mouth, ears etc.?" The argument from design is, as we've seen, an argument from analogy. All analogies end somewhere; otherwise they wouldn't be analogies. By saying that the relation from A to B is analogous to the relation from A* to B* that we postulate, we are not asserting that B* has all the characteristics of B, but only those that account for the existence of the relation and also the others, unless we have empirical evidence to the contrary. To account for regularities through the activity of a god, that god must be free, rational and very powerful. But it doesn't have to be the case that, like man, he can only act on a limited part of the Universe, a body, and in so doing control the rest of the Universe. And there is good reason to suppose that the god does not operate in this way. For, if his direct control were confined to one part of the Universe, scientific laws outside his control would have to operate to ensure that his actions had effects on the rest of the Universe. Thus, postulating the existence of this god would not explain the operation of these laws: yet explaining the operation of all scientific laws was the reason for postulating the existence of this god. The hypothesis that the god is not incarnate is therefore a better and more coherent explanation than the hypothesis that he is incarnate.”
