While relations among Christians are far more peaceful today than they were 500 years ago, the tension between theological particularity and yearning for universal fellowship is still just as complicated. As global Christianity evolves, the tension is likely to increase.
Especially over the last century or so, Christian groups have made significant attempts to repair the conflicts among them. In the mid-19th century, the Evangelical Alliance sought to unite Protestant groups to oppose child labor and poor factory working conditions, a unity they described as “a new thing in church history.” In 1910, a missionary conference in Edinburgh laid the groundwork for what later became the World Council of Churches, which united many Eastern Orthodox, Anglican, and mainline Protestant churches for the first time.
But until recently, the rifts of the Reformation were insurmountable. “The idea that Catholics and Protestants would get together to cooperate on anything is just almost unimaginable before the 1960s,” said Mark Noll, a historian at Notre Dame University. “In my lifetime, there has been a sea change in Protestant-Catholic relations, opening up an unimaginable array of cooperation.”