Church Membership Revisited

In the past month while I have been too crazy busy to write, the blogosphere has been alive with the Grudem-Piper discussion of church membership and baptism. So, I figure I can plunge in in the wake of the other million-plus bloggers!
The issue, I think, has been very much clouded by references to the universal body of Christ and the doors of heaven, etc. Let us ask this question: Are there people who claim to be Christians and are not? The New Testament makes clear that there are. And there are even church leaders who are wolves in sheep's clothing. So how do we mark out those who are not real? This has traditionally been done by confession. The course of church history has been the refinement (note: not the invention) of these confessional points. But with the postmodern rejection of propositional truth we have arrived at the idea that these confessions are moot.
Today there are many people (i.e. Ted Kennedy, John Kerry, et. al.) who call themselves Roman Catholic but do not agree with the Pope's position on human reproduction. The problem is that to be a member of their catholic church you have to believe what the church teaches or you are a heretic. And the church teaches that the pope is infallible. Ergo, if you believe that abortion is OK then you are a heretic in the eyes of Rome. The problem is that the Roman church has lost all it fire to tell people that kind of thing. Not to mention they have lost the moral ground to talk to others about their morals.
But confessions are important. The history of modern american evangelicalism was the confession of the truth of the gospel against modernism's refutation of inspiration, inerrancy and miracles. So there has to be a confession of some absolute truth by a person before they can be considered to be a christian.
Also, early in church history we see a division of the visible church over cultural and interpretational issues. Let us not forget that the Roman and Greek churches were greatly divided hundreds of years before the Pope and the Patriarch excommunicated each other. But until that open divide the differences did not hinder the churches from fellowship and agreement on the major doctrines: Trinitarianism, Christology, Pneumenology, etc. The protestant reformers could not even come to an equitable understanding about the eucharist!
Personally, I have recently joined a baptist church after 12+ years in a bible church. I am not particularly ready to have the baptist distinctives tattooed on my arm! But I also believe that God Sovereignly led us to a baptist church so I don't fight against them. If God had placed us in a town where the only bible-preaching church was a Wesleyan Brethren assembly I would not be trying to convert them all to the doctrines of grace! So why would a presbyterian want to join a baptist church and not be baptized?
What if it was the other ordinance? If you visited a church that practiced closed communion, would you insist that they allow you to participate because you believe in open communion? I think most would think it quite rude and uncharitable. Why would a divergent stance on baptism be any different?
Let us call it what it is: consumerism. People want what THEY want and they have a RIGHT to have it! I believe the Bible teaches that God is providentially ruling the world. Any church that is doctrinally sound that God places me in deserves my commitment and submission. If they are some place theologically that I am not then I need to submit to that. That means, if I were a preby and was sprinkled either as an adult believer or as a child, I would submit to submersive believer's baptism. Remember, part of submitting to Christ is submitting to the authorities God has placed in our lives. It is where the tire of divine sovereignty meets the road.