Most commonly, ecumenism is used in its narrow meaning, referring to greater co-operation among different Christian groups or denominations. For some however, it may also refer to the idea of unity: that there should be a single Christian Church. In its broadest sense, the unity may refer to worldwide religious unity; here the vision advocates a greater shared spirituality across Christian, Jewish and Islamic faiths. Mostly however, the term refers to the narrow sense, that of greater co-operation among Christian groups without aiming for unity.You can read the rest of that article if you want more background. So, generally speaking, this movement refers to the efforts of various Christian denominations to forge agreements of official partnership and cooperation, or (in rarer cases) organizational unity. A remarkable example of this movement is the full communion agreement between the Evangelical Lutheran Church in America (ELCA) and the Episcopal Church in the USA (ECUSA, now more properly acronymified as TEC, for "The Episcopal Church"). These major agreements are usually the result of years of discussion and negotiation between the leadership of the church bodies, and frequently involve controversial compromise. For example, as part of the ELCA/TEC agreement, ELCA Lutheran pastors can now be ordained only by bishops. This change didn't sit well with some Lutherans, to put it mildly.
Major organizations working to promote ecumenical cooperation and agreements include the National Council of Churches, the World Council of Churches, Churches Uniting in Christ, and Christian Churches Together. This is far from a Protestant-only phenomenon; the Roman Catholics and Eastern Orthodox are working on this, and many Protestant denominations are working with those two ancient bodies as well.
At the same time various church bodies are inching contentiously toward organizational unity, an opposite force seems continually to be at work within Christendom: organizational schism. Thus, where five years ago the Episcopal Church was the only official Anglican church body in the USA, now we also have the Anglican Mission in the Americas (AMiA) and Convocation of Anglicans in North America (CANA), which include formerly Episcopalian bodies which have broken away and are now under the oversight of overseas bishops. Similarly, it seems like just about every major Protestant denomination in the US has at least two organizational incarnations which have severed unity with each other over differences in doctrine and/or practice: The Lutherans have ELCA and LCMS; the Presbyterians: PCUSA and PCA; the Baptists have the SBC and the ABC (who themselves just schismed) and others, and the Stone-Campbell folks...well, read this. (There's a cautionary tale for the emerging church if ever there was one.) The Methodists in America are doing pretty well at the moment, unity-wise, but my Methodist friends are worried.
So what's my point in taking you on this whirlwind tour of organizational unity efforts and organizational schisms within the Body of Christ? Well, first of all, let me say that the former certainly make me happier than the latter. I'm sure not going to claim that working to set aside dividing differences between church bodies and create formal agreements of cooperation and partnership is a bad thing. Just as schisms aren't all bad (they can, potentially, allow warring factions to stop being consumed by the internal battles and get on with the mission of God), ecumenical agreements aren't all good (ask, for example, the pissed-off Lutherans from a couple of paragraphs ago) - but in general, I'm not opposed to high-level church leaders spending their time working toward organizational unity. I can think of better things for them to be worried about, but I can think of worse ones, too. So, y'all be about that, bishops and whatnot. Maybe it'll keep you out of trouble.
But, my real point is directed toward you rank-and-file priests and ministers (by which I mean every single follower of Jesus, in case you didn't click through those links just now). If you're listening, folks, here's what I think about ecumenism:
The ecumenical movement is a fine thing, but for the love of God and God's mission, don't wait for it. Don't sit around like a spectator at a sporting event waiting to find out who will win in the end: the forces of unity ("Score! The Episcopalians and Movians have forged an agreement!") or the forces of schism ("Touchdown! Conservative Methodists break away from UMC!"). This game is gonna be going on for an awful damn long time, and quite frankly, IMHO, it fundamentally doesn't matter. The Body of Christ is already one.
Let me say that again: the Body of Christ is already one.
Among the breathtakingly beautiful "farewell speeches" of Jesus recorded in John's Gospel (words given to his disciples on the eve of his arrest and crucifixion) exists this passionate prayer of our Lord (John 17:20-26):
20 "My prayer is not for them [Jesus' current disciples] alone. I pray also for those who will believe in me through their message, 21 that all of them may be one, Father, just as you 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. 22 I have given them the glory that you gave me, that they may be one as we are one— 23 I in them and you in me—so that they may be brought to complete unity. Then the world will know that you sent me and have loved them even as you have loved me.
24 "Father, I want those you have given me to be with me where I am, and to see my glory, the glory you have given me because you loved me before the creation of the world.
25 "Righteous Father, though the world does not know you, I know you, and they know that you have sent me. 26 I have made you known to them, and will continue to make you known in order that the love you have for me may be in them and that I myself may be in them."
You may disagree with me, but my personal, deeply-held conviction is that when Jesus prayed this prayer, he wasn't praying that some human institutional bodies in the third millennium would manage to forge agreements of organizational partnership at a rate faster than those same institutions were schisming. Verses 25-26 above, as well as my beloved John 13:34-35, explicitly tie our Lord's vision of unity to the mission of God, and make this loving unity the hallmark and fundamental characteristic of the Church. It's not optional, and it's not something we can undo. We can (and do) act like we're not one Church, but I'm pretty deeply convinced that we are one Church: one holy catholic and apostolic Church, as the Nicene creed puts it.
The unity for which Jesus prayed, in my opinion, has JACK to do with organizational/hierarchical/institutional unity. It has everything to do with loving one another - despite, or better yet celebrating our differences.
So please, please, please don't wait for organizational leaders to negotiate an agreement between church bodies before you start actively loving and working with your sisters and brother in Christ, regardless of organizational/denominational affiliation. We are one Church, and we really just need to start acting like it. Make friends across denominational and organizational boundaries, and where those friendships begin to bear missional fruit, go with it unhesitatingly. (We should be making friendships as well with people of other faiths and of no faith, and celebrating the fruit of those friendships as well - but as I said, within the Body of Christ I believe this is fundamental to our identity as a Church.) Worship together, serve the poor together, break bread together, theologize together, heal together, create art together, study Scripture together, grow together, goof around together, learn and teach together, and preach the good news together - celebrating the fact that you do all these things in different ways. Don't wait for your leaders to declare "full communion" - we are one Church. Let's love one another - as Jesus prayed - that the world may know God's love in Jesus, and Christ's love in us. Amen, and amen!