What makes this definition odd, especially in reference to Presbyterians, is that (Tim) Keller has been involved in the recent debates over subscription within the PCA in ways that have expanded the boundaries. …it would be hard to read Keller’s understanding of the PCA or his presence in those debates as placing him on the side of tightening the PCA’s boundaries.

If this were a joke, the punchline might be, “only Tim Keller’s hair dresser knows for sure.” Ba dop bop!

I understand that this question might wind up some readers, especially those who think the Gospel Co-Allies do no wrong. But it is one that need not be pejorative. It could say good things about the Gospel Coalition, for example, that it resembles the PCA. Since the latter is still a Reformed church and Reformed churches are good things, a comparison between the Coalition and a Reformed church could be positive. Of course, the answer to the question could go the other way and liken the PCA to the Gospel Coalition, a parachurch agency that fancies itself Reformed.

The reason the question could go either way is the lengthy explanation that Tim Keller and D. A. Carson gave (though the text uses the first person singular several times) to the recent imbroglio over James MacDonald’s invitation to T.D. Jakes. They distinguish between a “boundary-bounded set” and a “center-bounded set,” and claim that the Coalition has always been a center-bounded institution. I’m still scratching my head over these concepts. They sound more like sociology than ecclesiology and I tend to be skeptical when ministers or theologians employ jargon outside their own expertise. Be that as it may, the use of these concepts does not necessarily clarify the difference between a parachurch agency like the Coalition and a Reformed denomination like the PCA.

First, the nature of a boundary-bounded body:

. . . you establish boundaries to determine who is “in” and who is “outside” the set—whether the set of true believers, or the set of faithful Presbyterians, or the set of evangelicals, or any other set. For the boundary to have any hope of doing its job, it has to be well defined. If the definitions are sloppy, the boundary keeps getting pushed farther and farther out.

What makes this definition odd, especially in reference to Presbyterians, is that Keller has been involved in the recent debates over subscription within the PCA in ways that have expanded the boundaries. Even if someone wanted to interpret the recent changes in the PCA’s constitution in a conservative manner, it would be hard to read Keller’s understanding of the PCA or his presence in those debates as placing him on the side of tightening the PCA’s boundaries. In which case, I wonder if Keller really sees that big a difference between boundary- and center-bounded identities.

Next comes the center-bounded conception:

. . . center-bounded sets don’t worry too much about who is “in” and “out” at the periphery. Instead, there is a robust definition at the center. For TGC, the center is defined by our Confessional Statement (CS) and Theological Vision for Ministry (TVM) and sustained by the Council members. There we expect unreserved commitment to these foundation documents.

This still sounds to me like a boundary-bounded set up. But what makes this different is that no one can join the Coalition.

Individuals and churches may choose to identify themselves with us and use the thousands of resources on our site, but Council members do not fall into paroxysms of doubt as to whether or not this individual or that church truly belongs to TGC: we are not a denomination, and we do not have the resources to engage in the kind of vetting at the periphery that a boundary-bounded set demands. At the margins there are many who love part of what we stand for and not other parts.

So it would seem that the big difference here is membership. The PCA has members and the Coalition doesn’t. This gets confusing because Keller and Carson, among others, are “Council Members” of the Coalition. Why some parts of the Coalition have membership and others don’t is a mystery.

Yet, the same thing — that some in the PCA love, Keller included, parts of what the denomination stands for and not other parts — can be said of a denomination or a boundary-bounded set. In fact, it is true of most Reformed churches. In which case, Reformed churches may actually be much more center-bounded than the Coalition, except that the center of confessional Reformed Protestantism happens to be much bigger than the Coalition’s center, and for that matter, more biblical because the Reformed confessions try to do justice the whole word of God, not simply the bits about which guys from different denominations might agree.

One last similarity comes when Keller and Carson describe the diversity of ministries that exist outside the Coalition among the various “members’” activities:

Within these bounds, Council members discharge ministries that are highly diverse, with their own networks, specific aims, and relationships with many people outside the Council. Sometimes these relationships make other Council members uncomfortable. A Council member may choose to participate in discussions with an organization known for its laxness in doctrine and practice. He may do so in order to serve as a voice for faithful Christian confessionalism within that organization. Looking at this ministry, other Council members might evaluate things differently and warn the participating Council member that he is merely being used: it would be wiser for to avoid the association. But those are judgment calls. TGC does not normally take any position on whether a Council member’s associations are wise or expedient, even though there are not a few Council members who will offer their private judgments out of genuine affection and concern for gospel fidelity and clarity.

“Within these bounds”? I thought the Coaltion was center-bounded, not boundary-bounded. Be that as it may, this description of ministry diversity could also well apply to the PCA where the ministers who belong to the denomination have any number of ministries beyond the denomination’s. Think of New Life Presbyterianism and the different agencies that this wing of the PCA sponsors. Think of the Perimeter Church of Atlanta. Or how about Briarwood in Birmingham, Alabama? But speaking of Elephants in Rooms, what about Keller’s Redeemer Presbyterian Church? What about all of the networks that Keller has established?

Which leads to the question that I asked at the outset: how different is the Gospel Coalition from the PCA? Judging by the Tim Keller’s involvement in the Gospel Coalition and the PCA, not much.

P.S. I might actually have received more counsel on these musings from the Coalition if the Keller-Carson post had been open for comments, but not even Justin Taylor’s post about the statement permitted discussion. I guess the indirect rebuke to MacDonald was all that the Coalition could bear.

D. G. Hart is an elder in the Orthodox Presbyterian Church, serving on the session of Calvary OPC in Glenside, Pennsylvania. Darryl blogs, along with his partner in the venture, John Muether, at Old LIfe where this article first appeared. It is used with permission.