If you didn't click the link, I questioned the use of the term "orthodox" to describe a conservative ethical standpoint with regard to homosexual relationships. My point was that orthodoxy has historically been used to describe agreement with the historic Christian creeds - especially their definition of the Trinity and of how Jesus was human and divine - the Incarnation. In contrast, ethical issues have been matters of debate throughout the history of the church, and a key current debate centres around how we should understand same-sex relationships. Ironically, at the New Wine conference in the summer of 2006, I had noted that the speaker had talked about Jesus in terms that (at best) were perilously close to adoptionism without any comparable furore about a lack of orthodoxy.
Now there's an important note to make here. Ethics is related to theology, and theology has ethical consequences. The distinction is not as sharp as my opening gambit might suggest. However, it is indisputable that Christians have differed on a variety of pretty important ethical issues without necessarily resorting to labelling each other heretics / unorthodox.
Take, for example, the question of the use of force. Pacifists would argue from Biblical texts such as the prohibitions to kill in the ten commandments (Ex 20:13, Deut 5:17) and Jesus' injunctions to turn the other cheek and love our enemies (Matthew 5:39,44). Others would draw on other texts to assert that military service is accepted (e.g. no criticism is offered in Mt 8:9, and soldier is used as an image in 2 Tim 2:3-4) It is deduced from other principles that defending the innocent and order of the state is a common good. There is a long track record of Christians concluding that where necessary, the use of force and taking of life can be justified. This was developed into what is often called just war theory.
My question is this: would we refer to someone on one side of the argument or the other as a heretic? Each is considering Scripture very carefully and thoughtfully, but they have drawn different conclusions.
Some would say to me that this issue is different from questions of sexuality. They would assert that the clear view of Scripture is that same-sex relationships are a no-go area, and those who say they could be are just swayed by the times. It's worth noting that early Christians were essentially pacifists until Constantine took power, but as emperors, kings (and later presidents!) claimed Christian faith, the use of force became not only accepted, but even actively encouraged. There is a case for saying that politics and power had a role in changing that ethical standpoint too.
Whether you're a pacifist or not, or whether you are socially conservative or liberal, I have a simple plea. There are people on both sides of these debates who are sincere, thoughtful, conscientious people trying to discern the will of God. All kinds of factors bear down on all of us to read our Bibles with some degree of selectivity. We set aside some texts, because we see principles from other texts as overriding them. Why else do some Christians allow divorcees to remarry, why don't we sell all our possessions, and why do we allow women to lead - let alone preach in church? The answer is that we bring other factors to bear to set those commands and prohibitions aside - the context of the passage in the wider text, the people it was written for, the issue it was addressing and so on. It's all about the delicate and complex art of interpretation or hermeneutics.
So by all means disagree over same-sex relationships, just as Christians have disagreed over other matters - including life and death for centuries. My plea is simply that we should avoid describing those with whom we disagree as unorthodox or heretical. To do so is to make a claim of authority that I, for one, am not prepared to own.