Again, I appreciate your response and would like to offer some thoughts on what seems to be one of the major points in your response: adherence to tradition.
...believers can deny a view the church has held for 2000 years and think he or she is doing so because he/she has looked at the texts with fresh eyes – but it’s just possible that he/she is looking at the text through the lenses our culture has provided for determining truth.
...Here we are in the first part of the 21st century for the very first time in history denying two thousand years of tradition. And it’s only in a Western culture that some of the church is doing so.
...Why is it now that we have come up with such novel and creative ways to understand these texts? What is it about our time that has brought us to believe what no representative Christian body has ever believed before? And what is it about our culture that has led us to accept what the vast majority of Christians outside of the west presently reject? It’s a belief that we know better. It’s a belief that we have progressed and others have not.
You are certainly right to point out that a progressive view of the Bible and homosexuality (I only use "progressive" to describe this view because that's how you described it) certainly comes, at least in part, from being influenced by a culture in which same-sex practices have come to be seen as morally acceptable by many people. While I have felt and, to a lesser but still significant degree, still feel somewhat nervous about making such a huge shift in Christian sexual ethics, I have come to see that the "for 2000 years" argument has much more emotional and rhetorical force than logical substance.
I guess the biggest problem for this line of reasoning is that it could be used to also deny previous major shifts in Christian ethics, the two most substantive being our changing attitude towards slavery in the mid-19th century and towards women in the mid-20th century. Let's just focus on the analogy with the status of women. Everything you said above could be, and certainly often is, said in relation to keeping women second-class people. Although I am not sure, I suspect that you are in agreement with the UMC that women can be pastors (please correct me if I am wrong). The shift among many Christian denominations in the West that has taken place over the past 50 years is one that had to reject nearly 2000 years of tradition, and this shift was undoubtedly influenced by our society's growing acceptance of gender equality.
I think sometimes we have to admit that the non-Christian world can get things right that the church misses. Christ fills the cosmos, and God's Spirit blows where it will, so truth isn't limited to those of us in the church. Sometimes we need to be open to learning what God's Spirit might be saying to us through the broader culture. This was certainly the case with women's rights. Also, the church's acceptance of full gender equality required some "novel and creative" interpretations of several things Paul said about women. I would be the first to argue that Paul went along ways towards gender equality in his time and culture, but the fact is that he also said some things that require some deep exegetical considerations to get around that have not been embraced by 99% of our church tradition.
So, I agree with the main thrust of what you said, namely, that progressives have not reached their conclusions by Bible study alone. However, I disagree with the implication you make from this, namely, that progressives are doing something illegitimate when they let their culture influence how they read the Bible. We certainly did this when we changed our mind about women, and I would hope you would agree that it was a good thing we did.
Also, one indication that progressives are not being influenced by culture alone, but by deep biblical values as well, is that many progressives (such as myself) still uphold norms of monogamous fidelity for same-sex relationships. This, obviously, goes against the grain of our culture's sexual ethics which, as you say, has as its only taboo no overt and immediate harm. Our culture in many ways suffers from a great deal of confusion about what authentic and whole sexuality looks like. I am just finding it impossible to say what the harm is in two people of the same sex loving each other in a covenanted partnership for life. When it comes to other things, such as our culture's increasing acceptance of pornography and promiscuity, it isn't hard to point to why such things are destructive for individuals and families. So, while I have no doubt I been influenced by culture on this, its hasn't been a blind and uncritical influence. In my own thinking and living, I swim upstream on a number of issues, and perhaps even swim upstream (at least in some circles) in insisting that fidelity be a central norm for sexual ethics.
The slavery and women examples suffice to show that the "for 2000 years" argument isn't sufficient in and of itself, and if we adopted a principle that said that we should not go against established tradition, there would never be any such thing as moral progress. However, there is an important counterpoint one can raise here. Although the Bible does have passages that condone/endorse slavery and the subjugation of women, it also contains passages that do point towards a more liberating view. So, Christian abolitionists and feminists had a few verses they could put in the arsenal to fire back at the traditionalists. However, the Bible contains nothing positive whatsoever to say at all about same-sex relationships. I believe the five explicit biblical prohibitions of same-sex intercourse are very difficult to interpret, in terms of discerning their range, scope, and the assumptions behind them. But any honest interpreter of Scripture must acknowledge nothing overtly positive about such relationships in the Bible. (In my mind, appeals to the Roman centurion's slave, David and Jonathan, and Ruth and Naomi don't go very far in this regard.)
If a Christian is going to argue for gay marriage, she/he would have to do it on grounds other than direct scriptural appeal. But Christians have formulated a number of theological or moral principles for which there is no direct scriptural appeal. Take, just as a random example, the belief in an "age of accountability." Most Christians believe now that all children go to heaven if they die before reaching this age, usually thought to be around 13 or so. This belief has no direct support in Scripture at all. It makes sense and is accepted because it seems to be an outworking of more general biblical convictions about God, namely, that God is just and good, and it wouldn't be just or good to punish children forever. I am not arguing that we shouldn't believe in an "age of accountability." I am just making the point that if you require direct scriptural support for a conviction, you are setting the bar so high that some of our most deeply held convictions wouldn't make it past that requirement.
Most Christians have come to see heterosexual marriage as primarily about an intimate bond of friendship between two equal people who have voluntarily entered into the life-long relationship. (This way of thinking about marriage, by the way, is itself a huge shift from previous cultural definitions of marriage. Contrary to what politicians say, marriage is the social institution that has changed the most over time.) Most Christians do not think that procreation is necessary for a marriage, and the church and the state bless and legitimize heterosexual unions that have no intent of having a child. With the account of heterosexual marriage that many Christians have come to endorse, it has become much more difficult to give a principled reason (as opposed to a mere prejudiced assumption) why homosexual people should be excluded from such a marital arrangement. If marriage is primarily about celebrating and upholding interpersonal love in a life-long covenant, what it is exactly that precludes two men or two women who long for intimacy with one another from participating in this institution?