“We are to allow one thing to be really and truly distinct from the other, to be its own genuine self. There is a logical and philosophical urge in thinking men to reduce all things to a single unity. But this urge of the natural reason tends to petrify the heart. There is no single essence to which all existing things belong, no single essence which makes all things basically one. The only true unity of created things is the unity created by love. The heart embraces all things in their great variety and the heart loves them all.” -Arnold Albert van Ruler (God's Son and God's World, 64)As van Ruler points out, there is a tendency among us "...to reduce all things to a single unity." The tendency is strong enough that we may even be offended by van Ruler here. Is it not true that, at some basic level, we're all made of the same stuff? Is there anything human that's truly alien to any human? How could we empathize with one another if we couldn't in some sense share a single unity? And didn't St. Paul himself write, "There is neither Jew nor Gentile, neither slave nor free, nor is there male and female, for you are all one in Christ Jesus"?
Herein lies the tension of human unity and diversity, not to mention Christian unity and diversity. Whatever unites us cannot subsequently exclude us or anyone else in who they really are. In Christian unity, we are united in Christ. The standard which unites us belongs not to any of us, and yet we are bound to it, by it. There is a sense, in humanity and Christianity, in which we are all made of the same stuff. We are all, if nothing else, broken... and in Christian unity, we're accepted in our brokenness. We are not united in our sameness, although it may be that something is shared, and we are not united in purity--purity which unites by way of exclusion. We are not united without difference. In whatever sense that "we are all one in Christ," it is by no means by way of flattening, conflating, or reducing humanity to some single unity of perpetual similarity. No. "The only true unity of created things is the unity created by love. The heart embraces all things in their great variety and the heart loves them all." Our true unity comes to us as God's acceptance of us in our fractured and broken human existence. We are not united by our love for God, we are united in being loved by God, a love which embraces the variety of difference.
What's difficult about this, what's difficult for Christians to swallow, is that Christianity thusly does not imply a special conduct attributed to uniquely to Christians... although conduct must follow grace. In being accepted in our difference and in being united in being accepted, it does not follow that Christians are in any way moral superiors to anyone else. The Christian may recognize the acceptance of God received by all even where some do not recognize it. But the Christian is not unique in any other sense. That is to say, we do not have any outright claim of ownership on the good or the beautiful. Christian unity is not a unity of purity or a unity of sameness which excludes difference. Christian unity is the unity of the Christ, the universal love of God for all people. We are clothed in this. There is no standard we must reach or approval we must seek. We need not reduce ourselves to a single unity. But what becomes fundamental to us is that we are loved in our multiformity... and in this we are united.
What does this mean, however, for churches? Is this not so passive that anyone should feel comfortable in a church, even if they are profoundly exclusive in their conduct and ideology? What about justice? As I said, conduct must follow grace... it is indeed anticipated by it. Therefore, a Christian community eventually desires to be the ambassador of this unity in difference. Its conduct is meant to correspond to that radical grace of God in some way. The Word of God is proclaimed in the church, and this Word, as a word of acceptance, is a word which rejects our exclusivity, excommunicates our excommunicative impulses, and convicts us in our acts of marginalization. It is not so passive. We are commissioned, perhaps paradoxically, to witness to God's love in the world with our actions. But these actions are not the prerequisite to Christian unity, they are the response to it. We don't act out of the compulsion of pragmatism, we act as the logical response to being unified in our difference. We speak against sin and advocate justice because sin and injustice are not compatible with our having been accepted. I am reminded of something Kenda Creasy Dean once wrote which is, I think, descriptive of Christian social conduct, "With God's breath in the church we are called to exhale, but not because it's a morally good thing to do but because we can't help ourselves" (Dean, Almost Christian).