Carl R. Trueman is a Christian theologian and church historian. He is Professor of Historical Theology and Church History and holds the Paul Woolley Chair of Church History at Westminster Theological Seminary. He asks all the right questions in an article entitled so may it be!’ seem somewhat curmudgeonly. Thus, when Peter Leithart opened last week’s discussion on the future of Protestantism by lamenting ecclesiastical disunity and expressing a desire for a visibly united church, there was an audible murmur of support and appreciation from the audience. I knew immediately I would emerge over the course of the evening as the nay-sayer.

I agree with Peter that unity is much to be desired. But two questions remain for me after the discussion and the various blog posts: What does this unity look like? And how do we get there? Claiming that God can slay and resurrect the church is true enough. He can also cure cancer by a mere act of his will. But, if diagnosed with such, I am still going to drive to the hospital to receive chemotherapy.

Peter offered an attractive and humorous vision of church unity, involving (among others) hierarchical Baptists, disciplined Anglicans, jolly Presbyterians, and practitioners of paedocommunion existing in harmony. The vision was humorous, though intended as more than mere jest, I think. The problem is that it cannot possibly be realized (and that not simply because the idea of a jolly Presbyterian is self-referentially incoherent): There can be no visible institutional unity in terms of liturgy or theology between Baptists and Paedobaptists, let alone between Baptists and practitioners of paedocommunion. Thus, the question: What will this unity look like in practice?

Peter did present a more practical vision of local churches talking and fellowshipping together. That already happens in many places, so I suspect he actually wants more, something with a definite liturgical and institutional expression. If that is the case, then numerous other questions arise, the first of which I posed on the night of the discussion: Where do we draw the boundaries for this fellowshipping into unity? Peter’s response seemed to be that we set the borders in terms of Nicene/Chalcedonian orthodoxy. That is a good answer in some ways, though it does appear to demand the relativizing of everything subsequent to that (and thus that Roman Catholics and Protestants regard that which gives them their doctrinal distinctiveness as basically negotiable).

That answer also leads to further, more pointedly practical questions: When do I close my church down and tell the people there to start attending another Nicene/Chalcedonian church in the locale? What precise criteria do I use for making that call? When does my church’s continued existence become an act of divisive schism (a question easy for Roman Catholics to answer, but what about Peter?). The town where I pastor has a Roman Catholic Church of impeccable Nicene orthodoxy. Do I serve any good purpose as a Presbyterian in that place? And if I do serve such a purpose now, what exactly is that purpose and when will I know that it has come to an end? (As an aside, this also points to the fact that, while Protestantism cannot be reduced to doctrine, doctrine is fundamental to its present identity and, indeed, to its very reason for existence in the first place).

There are questions here for Fred Sanders, too. At some point in the discussion, he stated that we should rejoice that the Eastern Orthodox Church spreads the knowledge of the Trinity. Indeed we should. But how much should we rejoice? Rejoicing in word only is not really rejoicing at all. Joyful action must surely be part of it. So do we rejoice to the point that Protestants cease to plant churches in parishes with Orthodox congregations? If not, why not? Or do we rejoice to the point where we even close down established Protestant churches in such parishes? The prioritizing of the doctrine of God over against the doctrine of salvation which seems explicit in Peter’s Nicene proposal and perhaps implicit in Fred’s attitude to Eastern Orthodoxy, is a move that I cannot make without ceasing to be Protestant and giving up all that makes me doctrinally distinctive. But should I nevertheless do so? Are the doctrinal differences over salvation simply not important enough for me to keep my church doors open when there is an Eastern Orthodox church across the street?

Discussions of church unity are so often an example of incontestably admirable aspirations combined with a complete lack of practical suggestions. Discussions of the future of Protestantism can tend that way too unless we ask the basic pragmatic questions of what we want to achieve and what steps we must take to achieve it.