I agree with Cappadocious' points. Mostly. But to claim that human parents are called father because they are kinda like God the Father makes excellent theology but lousy etymology. It's reasonably clear that the primary meaning for the word "father" is human fathers, and it was applied to God because of the similarity.
Forgetting the word we use, I agree that God came first. We are in his image, so human parents have a function that at its best will suggest God's function. And I agree with him that this is true of both human male and female parents.
But if we're asking what English word to use for God, it's pretty clear that the human meanings came first. Given that both human male and female parents carry out roles that originated in him, I think it would in principle be appropriate to use either word. We don't, typically, because we're normally following Biblical precedent. And that's just fine. I don't suggest that we change the titles of the Trinity. But to the extent that we use human words, human analogies and human images, I believe it is appropriate to use those taken from both genders, since both genders reflect God. It actually seems heretical to me to say that God is male. It reflects either the idea that God has a biological gender, or that males somehow are more in his image than females.
C S Lewis is fairly well known for saying that while God isn't male in the human sense, there is a spiritual analogy, in which he is even more masculine than any man.
"Gender is a reality, and a more fundamental reality than sex. Sex is, in fact, merely the organic adaptation to organic life of a fundamental polarity which divides all created beings. Female sex is simply one of the things that have feminine gender; there are many others, and Masculine and Feminine meet us on planes of reality where male and female would be simply meaningless. Masculine is not attenuated male, nor feminine attenuated female. On the contrary, the male and female of organic creatures are rather faint and blurred reflections of masculine and feminine. Their reproductive functions, their differences in strength and size, partly exhibit, but partly also confuse and misrepresent, the real polarity."
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http://www.touchstonemag.com/archives/article.php?id=04-01-005-f#ixzz4EJpZIve1]
I would say however that there is a problem with this. Actually, not in this specific quote, but in the fact that he ended up saying that God is specifically masculine in this deeper spiritual sense. God may in fact be masculine in a deeper and stronger sense than human males. But I think we ought to consider that he might be feminine in a deeper and stronger sense than human females. If we don't say that, then we're saying that males are most strongly in God's image than females, and I think that's seriously wrong. This is *not* saying that there is no difference, by the way.