There has been some discussion about why organizations like Together for the Gospel and The Gospel Coalition include a complementarian clause in their confessional statements (see their respective videos here and here). Carl Trueman speaks for many when he says he is confused by this emphasis on gender roles. He writes,
[W]hy is the complementarian/egalitarian debate such a significant bone of contention in parachurch cobelligerent organisations whose stated purpose is to set aside issues which divide at a church level but which do not seem to impact directly upon the gospel? Why, for instance, is this issue of more importance than, say, differences over baptism or understandings of the Lord’s Supper? Historically and confessionally, those have been the issues that divide, so it is strange to see the adjective ‘confessional’ applied to movements which actually sideline the very doctrinal differences which made Protestant confessions necessary in the first place.
This is not a new question, however; and Denny Burk gives an answer in the form of a metaphor:
Every year I visit my dermatologist for a check-up. In those examinations, he looks at everything growing on or under my skin to see if there is anything that needs to be removed. Every year, he observes a number of moles, skin tags, and other unseemly blemishes. For aesthetic reasons, he’ll sometimes suggest that I have one or more of these blemishes removed—a suggestion that I typically refuse. On two occasions, however, my doctor has identified “blemishes” that he insisted must be removed because they were precancerous. I rely on the doctor to distinguish the benign blemishes from those that will develop into something that is malignant. Neither type of blemish will kill me. But what grows out of the latter type of blemish can indeed end my life.
Differences over secondary theological issues are like those blemishes. By themselves, they are merely theological blemishes that do not necessarily threaten the central issues of the gospel. Like those blemishes, however, some of them have the potential to turn into a theological cancer. Some secondary issues have more deadly potential than others, and we all have an obligation to be able to distinguish the former from the latter.
Two reasons are given to explain why egalitarianism is likened to a cancerous mole. First, there is what I call the tortuous gymnastics objection as articulated by Lig Duncan:
The denial of complementarianism undermines the church’s practical embrace of the authority of Scripture (thus eventually and inevitably harming the church’s witness to the Gospel). The gymnastics required to get from “I do not allow a woman to teach or to exercise authority over a man,” in the Bible, to “I do allow a woman to teach and to exercise authority over a man” in the actual practice of the local church, are devastating to the functional authority of the Scripture in the life of the people of God.
Dear reader, you may not agree with me on this. And I don’t desire to be right in my fears. But it seems to me and others (many who are younger than myself) that this issue of egalitarianism and complementarianism is increasingly acting as the watershed distinguishing those who will accomodate [sic] Scripture to culture, and those who will attempt to shape culture by Scripture. You may disagree, but this is our honest concern before God. It is no lack of charity, nor honesty. It is no desire for power or tradition for tradition’s sake. It is our sober conclusion from observing the last 50 years.
I thinks this a great discussion and I left this response in the comments of Denny’s post:
Thanks for this post. Some thoughts in response. First the Duncan quote:
“The gymnastics required to get from ‘I do not allow a woman to teach or to exercise authority over a man,’ in the Bible, to ‘I do allow a woman to teach and to exercise authority over a man’ in the actual practice of the local church, are devastating to the functional authority of the Scripture in the life of the people of God.”
I’ve never understood why the tortuous “gymnastics” charge picks out egalitarians and not others. Are not the same broad principles applied to Jesus’s command “do not to resist an evil person (Matt 5:39) such that, when considering cases like rape, the victim is allowed “to resist an evil person?” The point is there is a time and place where this instruction holds and where it does not. Likewise, as egalitarians tend to read Paul’s restrictive passages, the purpose of the restrictions are explained as taking into account uneducated and contentious women. Again, we might disagree about this, but the authority of Scripture is not at stake; rather, it is our *interpretation* of Scripture. Just because someone holds a more expansive range of cases where an imperative applies does not mean one holds a stronger view of the authority of Scripture. We would not grant that to a hardcore pacifist; why should we grant this to Duncan? No good reason I can see.
Second, I think the sort of arguments which conclude “egalitarianism is a new path to liberalism” are flawed. They represent the so-called “track record” like this:
 If one holds to egalitarianism, then one (probably) undermines the authority of Scripture.
 If one undermines the authority of Scripture, then one is (probably) on a path to liberalism.
 There are people who hold to egalitarianism.
 Therefore, there are people who are (probably) on the path to liberalism.
Call this THE ARGUMENT. In order for THE ARGUMENT to go through, one has to show that premise  is true, that is, that holding to egalitarianism is a *causal factor* that, at least, increases the likelihood of undermining the authority of Scripture. But I think this is far from clear in light of the sizable contingent of scholars who truly hold to the authority of Scripture AND egalitarianism.
Obviously, holding to egalitarianism isn’t a sufficient condition for undermining the authority of Scripture (a la Roger Nicole). And of course, neither it is necessary. One can deny the authority of Scripture while rejecting egalitarian gender roles. Plenty of conservative Muslims and Jews do just that. Therefore, I think THE ARGUMENT would be better stated like this:
 If one does not hold to the authority of Scripture, then one is (probably) on a path to liberalism.
 If one is on a path to liberalism, then one (probably) holds to egalitarian gender roles.
 There are people who do not hold to the authority of Scripture.
 Therefore, there are people who (probably) hold to egalitarian gender roles.
Of course, evangelical egalitarians would agree with this argument, because the determinative issue is whether one holds to biblical authority–not egalitarian gender roles.