This is an important topic, and essential to understanding God's true nature. I've addressed this topic before but I use different approaches to help humans to understand a complex topic. Actually, it's not complex-it is very straightforward-but it is one of God's mysteries. By mystery I do not mean it is unknown or hidden, but rather, it is one of the things that are of the divine that humans find difficult to understand. So here is another discussion of this topic.
Notice that I say that God "manifests" himself as masculine. When I say "manifest" I mean that God chooses to present himself as masculine to humans because that is the most consistent with his nature, even though God is, as Pope Benedict has explained, all things in one, unable to be characterized as being "male" or "female" because he has both the maternal and paternal qualities, being all things and all complete. However, God has consistently presented himself as masculine and "The Father" in Jewish, Christian and Muslim holy books. God always appears in a masculine form and presents masculine characteristics, so one cannot say that it is "sexist" authors or culture to "blame." In fact, this is refuted in the Old Testament where the Holy Spirit is often presented as feminine Wisdom (see the Book of Wisdom). So if God chose to be presented as a female he would have done so, and done so consistently in all the monotheistic books.
So why does God present himself as masculine? Remember that humans are created in God's image, so you can think about the obvious difference between men and women regarding God's primary role, which is the creator of life. God is the creator of life, not the bearer of life. The Bible explains that God is all powerful and whatever God wills is instantly manifest. In other words, when God wishes to do something he does not have to "chant a spell" (follow a formulaic process) or "wait" while his will is gestated (such as the pregnancy of a woman, who bears a growing and changing organism). When God wills something, whether it is the initial creation of the entire universe (think Big Bang, for those of you who like the science connections where possible) or to the small things of communication with humans, it instantly "becomes" done. Jesus taught "God's will be done." This is not a gestation, peculating, waiting process. Whatever God wills is instantly done. That is obvious everywhere and in every way, and is explained over and over in the holy books. That is why Jesus is called "The Word," because God only "speaks the word" (wills something to happen) and it does, such as the conception of Jesus.
God therefore is the "masculine" principle in action, which is the seed from which all comes without waiting, bearing, gestating, working formulas and processes, or being the inert or co-operative container of life. God in his fullness is not compatible with a human perception of him being female because there is nothing about God that is gestating: his will at all times is instantaneous and complete.
Thus feminists and their pussy whipped male enablers have it all wrong when they try to force God's "nature" to be identified as being sexual in nature at all AND in forcing a partial or complete "feminine" ideology on him. God has consistently and always chosen to manifest as a masculine and Fatherly presence in the entire faith history from Adam to Jesus Christ, and also in communication with the Prophet (PBUH) through the Qur'an. This was abundantly clear as not being "sexism" to thousands of years of humans, and it is only this occult and narcissistic ego tainted past several modern generations that willfully do not understand and obey God's obvious strictures about how he manifests to humans. This is not a diminishing of the human female role at all. In fact it highlights the virtue of patience and the slowness of true growth when one looks at feminine biology as a parallel for spiritual growth and maturity. God "creates," God does not "grow." God wills, God does not "bear." God is the seed, and Jesus is the shepherd of the flock, while humans are the ones who are obedient to time, who change and grow in body and mind, from embryo to maturity and hopefully, old age. God is eternal and unchanging, and thus God the Father cannot be linked to the feminine principle of gestation, containment and bearing. God has maternal feelings, as God is the source of all love, of all goodness, of all emotions that humans can aspire to as best as they can. So God is the fullness of all of reality and all of the possibilities, but he does not "nest" them and he does not "bear" them; God wills creation and action and it takes place in the instant of his intention, not over a period of time. Humans take time to fulfill God's will because they are the ones who must grow and change, under the pulse of time, in order to live.
This is why Catholic priests will always emulate Jesus Christ and will always be celibate men. Catholic priests are the vocation of giving their entire lives over to the will of God and emulating Jesus Christ, God's first Christian priest. This is why there is no dishonor in the many other holy offices and vocations available to women. The road of Catholic priest is the one that is taken by those permitted by God to most emulate his will and word with their very lives. Many men do not take that path, obviously, so it is not for everyone. It is a special and sacred calling and it has nothing to do with being "able to live without a family or sex." It has everything to do with being the ultimate narrow path that only a few men among all men will choose.
It also has nothing to do with diminishing the "spirituality" of women. Remember, as I've pointed out, the Holy Spirit, often appearing as a white dove, is often described with feminine nature. This is because the Holy Spirit, who is the breath of God among humans, operates and works "within time" in order to inspire, correct and fortify humans in both their faith and their bearing of life's burdens and joys. So the Holy Spirit, being of the nature of God, has the qualities of God but is manifest in constant interaction among humans, and thus can be thought of as a "bearing" and "gestating" manifestation of God. For example, the Holy Spirit may have to work an entire lifetime on a lost man or woman of the faith, or even of a nation, as we saw with the former USSR, and now we see in the People's Republic of China. The Holy Spirit moves among humans with qualities of patience and love that can be thought of as very feminine and of a spiritual gestation in individual humans and also among their communities. This is also the reason that the Church is described as the bride of Jesus Christ, in Christianity, and in the Old Testament, the faithful as the beloved of God. The body of the faithful, the groups of believing humans, are inspired and connected by the Holy Spirit. Thus there is a valid identification of journey, of child "bearing," of gestation, of "planting a tree" of a church, of being like how ships are often called feminine, because humans are always on a constant individual or communal journey toward God, and that is consistent with such notions and analogous examples. God himself, however, as the Father, is unchanging, complete as is, infinite and unknowable in all his eternal capacity, and instantaneous in his will and his use of his word to manifest anything and everything that he wishes. Thus one cannot think of God in any other way without distorting his nature, thwarting his will of how he presents himself to humans and, in fact, lying about God.
I really hope you find this helpful. The erroneous propaganda is only damaging and demeaning to humans and it really must stop as it takes you away from understanding God, rather than moving you toward him. The propaganda also lowers self esteem rather than raises it, because humans start to think of vocations as "career ladders" with mean religious people "thwarting them," rather than understanding the incredible heights that all humans have in understanding the true nature of God.