You can do lots of things with a SoF. You can not have one. Some no-creed-but-the-Bible Baptists think this is the way to go. You can also have one and ignore it—or at least ignore any semblance of historic continuity in the meaning of words. That'd make you a theological liberal, or maybe a contemporary, a-theological quasi-evangelical, cultural Baptist. And I suspect there may be lots of highly conservative Baptist churches in those two categories that are careless or simply don't think much about ecclesiology.
Those categories don't particularly interest me. Not today, anyway. Two other categories do:
1. Some Baptists use SoFs as a standard for leadership and public teaching but not membership. This approach is also common among elder-rule Bible churches and MacArthur-circle churches.
2. Some Baptists use SoFs as a summary of the minimum all members must affirm in order for them to function together as a church. I say "some." I'm tempted to say "most" SoF-users, if we were to count Baptists throughout church history, but I'll leave that to the bona fide historians.
My argument is that the latter option best represents biblical congregationalism. Why? Because the NT teaches that the congregation is responsible for the discipline and doctrine of the church. Not everyone agrees:
A doctrinal statement is not a requirement for church membership or ministry. A person may join a church being untaught, and not knowing enough to agree or disagree. A person may join a church agreeing to disagree. In such cases, the church can rightly expect that the member will not attempt to divide the congregation over the issues.Just one problem with that. Well, at least one problem. Who can join a church? Any professing believer? But a believer in what? The gospel? What's the gospel? Doesn't the gospel consist of things we believe—matters of faith? Can a convictional Presbyterian join a Baptist church? An open theist? An anti-inerrantist? Someone who believes Jesus was an ordinary man adopted by God and infused with the divine nature? Frankly, I suspect that all of these churches really do have a functional minimum common affirmation for membership, though they may not realize it. They just haven't faced a sticky situation yet.
Now, this approach might work in a baptistic, but minimally congregational elder-rule church, in which the congregation exercises no meaningful oversight in matters of doctrine. At least it might work for a while. But it's not at all difficult to see why an authentically Baptist, congregational church would be ill-suited to sustain its doctrine, regardless of what the present leadership is committed to teach. Church history is littered with examples of confessional churches and institutions that tragically abandoned their confessions. Are we to assume that a non-confessional church will be more stable?
A SoF in a Baptist church ought to be a minimum summary of what its members must commonly believe in order to function as a church. There's a worthwhile discussion over what needs to appear in that minimum summary. We should neither demand too much nor too little. But to diminish the significance of that SoF, whatever it does or does not include, is to undermine the very principles the SoF affirms.