Theologically, the catholicity of the church arises out of the incarnation of Christ. As Christ has identified himself with the whole of humankind through taking on human flesh, so his people are called to make his grace known through a costly identification with the world.
Implicit in the church’s catholicity is the call to embrace the whole world, to bring the gospel to people of all nations, classes and cultures and to incorporate them into its fellowship. To quote Geoffrey Wainwright,
The differences which nature provides in the matters of sex and race have often been hardened and distorted by culture to produce division and conflict. The catholicity of the Church’s calling gives room and encouragement for both sexes and all races to place themselves under the sovereignty of Christ, which means, when expressed on the social plane, the gift of self for the good of others and of all.
The challenge that confronts the church in every generation is to be able to distinguish between what is cultural (and therefore relative) and what is divinely ordained. If they are to survive (much less be true to their identity as “catholic”) in today’s society churches have to be able to communicate in a variety of cultural forms. They will be places where people’s cultural differences are celebrated.
This is far from taking the attitude that “anything goes”. Nor is it a matter of the church adopting an attitude of moral pluralism. It will involve pain for many, as they must let go of deeply cherished cultural forms in favor of making the eternal gospel more widely known. Yet the end result will be something that truly honors the Lord before whom every knee must one day bow—“a Christian fellowship that rejoices in its diversity, and where people of different races together offer themselves to God, to love each other and increasingly share their lives”.
While the church must be prepared to speak in the cultural language of its day, it also stands in critical isolation from that culture. Once a church has to some extent become contextualized, the temptation to an uncritical identification with the culture is always present. As a result its evangelistic witness is blunted and its prophetic message compromised.
While we must be careful not to identify the Christian faith with the cause of revolution, it must be conceded that there is a tendency for established congregations to become chaplaincies to their members, instead of engaging them in challenging the idols and shibboleths of the contemporary world.