In John 17, Jesus prays the following prayer for the church:
I ask not only on behalf of these, but also on behalf of those who will believe in me through their word, that they may all be one. As you, Father, are in me and I am in you, may they also be in us, so that the world may believe that you have sent me. The glory that you have given me I have given them, so that they may be one, as we are one, I in them and you in me, that they may become completely one, so that the world may know that you have sent me and have loved them even as you have loved me.
This text has always been foundational for Christians who are concerned about the unity of Christ’s church. But there are a broad variety of perspectives on what unity should be all about. As a kind of follow up to my post on the limits of legitimate diversity, I’m going to summarize six dominant visions of unity that cut across the denominational spectrum. They aren’t mutually exclusive, though some are definitely in tension with one another.
Spiritual unity: Evangelicals in particular have often emphasized that Christian unity is primarily a spiritual reality. This emphasis developed in response to the Catholic and Orthodox emphasis on “organic” unity as the goal toward which all churches should move, and also a way to bolster the legitimacy of protestant denominations as bona fide churches. This is a basic concept underlying denominationalism – the idea that the existence of separate church bodies is not contrary to God’s will, but an acceptable form of diversity, because underneath all our divisions we are spiritually one in Jesus Christ.
Visible unity: the call for visible unity has been paramount in the ecumenical movement. The call for unity to be “visible” stresses the fact that unity is not merely spiritual (i.e., “invisible”). In other words, our unity should be something that can be seen by those outside the church (obviously there’s a clear connection to Jesus’ prayer here – “so that the world may believe”). Some people equate visible unity with “structural” unity (below), or a denominational mega-merger, but that is not necessarily implied in the concept of visible unity. But real, shared fellowship, worship, and ministry are certainly part of any concept of visible unity.
Structural unity: Catholic, Anglo-Catholic and Orthodox visions of unity typically include a structural component, although none of these traditions would want to emphasize the structural aspect of unity as paramount. They would, however, insist on the idea that unity must include structures of authority, notably the historic episcopate. Other protestant traditions might also envision some structures of unity as being highly expedient or functionally important for the maintaining of unity.
Doctrinal unity: The spiritual unity perspective is often accompanied with some sense that there needs to be a baseline agreement on doctrinal “essentials.” For many, this means affirmation of the Apostles’ or Nicene Creed. Others might draw up a list of basics – the Trinity, the divinity of Christ, inspiration of Scripture, and so on. The flip side of this perspective is that anything that goes beyond the “essentials” is non-essential, and therefore disagreements on non-essentials are not church-dividing.
Unity in service: Another approach has tended to be characterized by the slogan “doctrine divides, service unites.” People promoting this vision of unity are wary of doctrinal dialogue between churches, and would rather focus on working together on practical issues such as social justice. The thought here is that most of our divisions are rooted in theological differences, and there isn’t much prospect of convergence on those differences.
Mutual Recognition: Some people feel that the church would be one if we could all recognize one another as legitimate Christian churches. This might not seem like a big deal for some Christians, but historically many of our churches have condemned each other and declared one another to be outside the boundaries of the church (think Luther calling the Pope the anti-christ). Some churches also have convictions about what it means to be the church which do not allow them to fully recognize other denominations as legitimate churches. Full recognition, of course, would involve recognizing one another’s ordinations and sacraments as valid. Great strides have been made towards mutual recognition, but there are still many Christians who do not recognize one another.
Koinonia: A growing number of ecumenical thinkers are focusing on the concept of koinonia as the best way to think about Christian unity. This biblical term carries a rich breadth of meanings, including communion, fellowship, participation, and sharing. The koinonia approach to unity begins with a conception of the Trinity as the divine koinonia, and stresses our koinonia as flowing from and being modeled on the divine kononia. We participate in the triune communion of perfect love, as God the Father draws us to himself through the sending of Son and the Spirit. The communion is therefore both “vertical” (between God and humanity) and “horizontal” (a communion that is shared with all who are in Christ).
This final concept has great ecumenical potential, first of all because it does not carry a lot of historical baggage. It’s not a concept which is “owned” by one particular Christian tradition. It also has great biblical foundations.
I wouldn’t want to exclude any of these concepts – the question is how they are related to one another, and where the priority lies. For example, I would agree that unity is a spiritual reality, but I’m not comfortable with the spiritual unity perspective if it’s just used on its own, or as a way of justifying denominational divisions. I’m still working through these issues now as I write my dissertation, so I don’t have any hard and fast answers, but I find it helpful as an analytic tool to lay out and compare these different visions of unity.