I really have trouble with the idea of joining a Church whose beliefs I don't entirely agree with, or more importantly, whose beliefs I am not willing to be shaped by in the future. Here I find Sinner Servant's reply to Liz's beautiful question appropriate:
It's all very well to say that a person must submit to the Church's teaching. And I accept that submission is possible when it applies to negative aspects (don't get into a homosexual relationship, for example), but how is it possible to force yourself into believing something you don't hold true?
Pray... "with tears, Lord, I believe; help thou mine unbelief." (Mark 9:24)
Joining the Orthodox Church without being willing to submit to the entirety of its beliefs seems to me oxymoronic.
On the topic of homosexuality, or sexuality in general... I think it is actually good that the discussion lingers on these topics because the fact is that these topics trouble a lot of people. They are a source of a lot of doubt evolving into unbelief, and it is for good reason that it has been the cause of schisms in many churches. It is not a peripheral issue, in my opinion, not because of its very nature, but because it causes us to face important questions that we otherwise avoid. What I'm trying to say is that though it is not a fundamental issue in and of itself, it causes us to face the fundamental questions that we avoid.
I have a theory on this, if I may indulge. A close friend of mine, a (faithful to Church teaching) homosexual (or bisexual), explains his struggles to me as follows: Imagine an engaged heterosexual couple engaging in sexual activity and conflicted about it. We love each other, but then our religious beliefs tell us we're wrong. What to do? In a few months, the couple are married, and the spiritual conflict tends to become moot. Whatever doubts they have about the doctrine are laid aside. The question may linger, but only in the abstract. The couple don't think about it much. It is not a source of spiritual struggle. But for the homosexual Christian, his belief is tested by his doubts throughout his lifetime, and he cannot turn away and avoid the resulting spiritual struggle. That is the constant struggle.
Or another more classic example... The dark night of the soul. For Mother Teresa, her perceived absence of God troubled her very deeply. It was a source of intense anguish. Whereas for others of us spiritual novices, with other things in our lives to occupy us, etc., it would not be so troubling. We wouldn't even notice it much, and if we did, we'd manage a way of not thinking about it too much. As the fathers say, the closer you get to God, the harder the Devil fights you.
Over the centuries, and certainly over the past few decades, many people who were Christians have come to reject Christianity. Their disbelief started out in various ways. The problem of pain, perhaps, or the evidence of science, or a variety of factors, all causing their experience and knowledge to clash with Christian doctrine. In the end, they decided that they simply could not believe the very idea of Jesus' divinity, reincarnation, etc. Like Bishop John Spong, they became some type of agnostic.
Interestingly, many of these folks tried to hang on to remnants of belief, while letting go of the doctrines they disagreed with. But slowly, yearning for philosophical consistency, they end up becoming non-Christian.
This is why I think that a 'cafeteria Orthodox', one that accepts some doctrine but rejects others, is simply in a transitional period towards complete unbelief. If one cannot, for example, believe scripture and the fathers on their teachings of sexuality, how can one believe their teachings on Christ's divinity, a matter far more fantastic and unbelievable than the teachings on sexuality?! Perhaps its because many of us think that we can safely and reject the teachings on sexuality, while maintaining our belief in Christ, because our doubts about Christ do not affect us personally. We are not like Mother Teresa - we can live with these doubts, avoiding them, not thinking about the too much. We are not like Spong, yearning for consistency.
I think the evidence over the last few decades supports the theory that 'cafeteria' or 'liberal' Christianity turns out to be a rest area on the road to agnosticism. The experience of the mainline Protestants shows that. Are liberal Christians frauds? Certainly not. They are sincere, but I would venture that they hang on for the sake of sentimentality. Beliefs don't change overnight. People and community are involved. One misses the friendship and the ceremony. One resists change. But in the end, the path they're on is the path they're on. And individual may persist in this limbo until he passes away, but over generations, a Church cannot. The Church slowly begins to disappear, and we're seeing this now.
This is why I think that it is important to understand that one has to submit entirely. One has to know what one is getting into. It is not just a community or buildings or people, but a well-formed set of beliefs that tinkering with simply does not make sense.