Some years ago, when my wife Carolyn and I lived and worked in Zaire, we came to appreciate if not to understand the Bapostolo. Their open-air worship services took place early on Sunday mornings right across the street from our little bungalow in the middle of the teeming Katoka district, part of the formerly Congolese (and poor) section of town. Men and women in white robes were surrounded by others in regular dresses and threadbare suits. Children were everywhere -- infants tied the backs of mothers and at their breasts, toddlers running among the adults, youth on the perimeter of the assembly. The Bapostolo were colorful in dress and noisy in preaching with a bullhorn. They were also fascinating in their singing.

The Bapostolo presented a stark contrast to the Presbyterian Church and other Protestant congregations with whom we worked. The service took place in Tshiluba, the tribal language of the region, so I could understand something of the Bible passages, but only a few of the other words and phrases they employed. When I walked across the street and tried to strike up a conversation with one white-robed leader after a meeting, he smiled at me and kept on walking.

When I asked one of the young people in our church about the Bapostolo, he explained that they read the Bible, sought to be Apostles of Jesus, and meant no harm even to non-believers. When I asked a Congolese colleague at the Presbyterian Centre de Jeunesse where we worked together, he said they seemed both indigenous and also from some other country, like the Senegalese traders who commonly passed in the streets.

“It seems they asked for our Bible, and then they wanted to read and interpret for themselves,” he told me.

“Are they Christians?” I asked.

“They claim to be, and they seem to do good job of listening to the Bible,” my colleague responded. “During the revolution, they were unwilling to shoot other people.”

Soon I learned this messianic-prophetic movement was led by John Maranke, who indeed had come from elsewhere. He had asked for Protestant translations of the Bible in Tshiluba, and his interpretation more than that of anyone else guided their life together. In those turbulent days in Congo Zaire, the mid-sixties when harsh Belgian colonial rule had ended to be replaced by violent inter-tribal warfare for the abundant resources cornered by Euramerican cartels, when Mobutu Sese Seko was consolidating power, Congolese were experimenting in ways of independence. The self-developed Bapostolo in the Kasai region of Zaire, central Africa were a natural development. Some of their practices seemed quite reasonable. Many seemed quite bizarre.

Again, were they Christian?

About that time, the Kimbanguists, another “tamer” messianic-prophetic movement from Congo, was seeking membership in the World Council of Churches.

“Don’t you worship according to the way Simon Kimbangu told you, and don’t you venerate him?” Many in the WCCC asked. “Don’t you pay little attention to the doctrine of the Trinity?” “How can you claim to be Christian?”

Kimbanguist leaders replied, “Don’t some of you follow in the footsteps of Martin Luther, or John Calvin, or John Wesley?” “Don’t some of you pay scant attention to the doctrine of the Trinity?” “Are you not in messianic-prophetic movement as well?”

My service as a Christian missionary made me broaden the boundaries for considering who is a Christian, how broad is the Christian movement.

I ask that question and remember the Bapostolo quite frequently today. For example, I think of them when I hear announcements for transcendental meditation groups, the yoga groups, and Eastern Star groups at churches.

When I worship at a church “letting out early” for a NASCAR event nearby. Or as in Cincinnati when the Bengals drew crowds years ago by renting busses to take churchgoers to Riverfront Stadium from the church parking lots.

When I share worship in a country church that only holds services on certain Sundays that also include afternoons of gardening in the adjacent cemetery.

Or in the wonderful congregation in which a refugee family has found a home -- a Shiite family that is. It even shares Lord’s Supper with the congregation.

Louis Weeks is president emeritus of Union Presbyterian Seminary in Richmond, Virginia, and author, most recently, of "To Be a Presbyterian" (Geneva).