They're not looking to marry, but you might say they're after long-term commitment--one that will lead to a sharing of ministers, communion and mission to the world.
The historic agreement reached here in July by Episcopalians and Lutherans was but one of many such alliances already sealed or in the works by the nation's mainline Protestant denominations.
Lutherans have similar full communion agreements with Presbyterians, the United Church of Christ, the Moravian Church and the Reformed Church in America.
Episcopalians have communion with the Church of Sweden and are hoping to open lines to the Pentecostal movement in this country.
United Methodists are having talks with historically African-American churches--the African Methodist Episcopal, African Methodist Episcopal Zion and Christian Methodist Episcopal churches. Those three denominations, all Methodist in nature and formed because of slavery, are talking about some kind of arrangement, maybe even union.
Even Roman Catholics are--somewhat, and sometimes uncertainly--on the floor. The Vatican signed an agreement last year with world Lutherans in which the centuries-old bodies agreed about a key belief of Lutheranism: justification by faith. It is the belief that people are saved by Jesus Christ, not by good works.
But it also issued a statement in early September saying the only sure path to salvation was through Rome and that other churches were "defective." The statement was widely perceived in the non-Catholic world as a new stumbling block on the road to unity. A week later, however, Pope John Paul II said the church remains committed to the ecumenical movement.
"The rewards of 30 years of careful dialogue are spilling out all over the place," said James Solheim, communications director for the Episcopal Church in New York.
Christians often quote one of the final prayers attributed to Jesus, when he prayed to God that all his followers "might be one so that the world may believe that you have sent me."
Despite centuries of division, unity is still a goal, but what it means has changed over the years.
As usual, the people are ahead of their leaders. There are dozens of united congregations around the country: Episcopalians and Lutherans share buildings; United Methodists, Presbyterians and United Church of Christ members share buildings and ministers. Christians go to one another's worship services, and many are no longer loyal to the denomination they were reared in.
Don Armentrout is one example. A lifelong Lutheran, Armentrout teaches church history at the Episcopal University of the South in Sewanee, Tenn., and for years has attended an Episcopal/Lutheran congregation because neither denomination can afford its own building and minister in Sewanee.
Despite that cost-saving alliance, Armentrout said the new alliances "aren't happening because of a survivalist mentality. The name of the game today is sharing ministry and mission and buildings and outreach."
For decades, Protestants, and sometimes Catholics, have belonged to councils of churches so they can work together on community projects.
The official alliances promise more solid, assured relationships.
"What's going on is utterly remarkable," Armentrout said.
Talks aren't enough, though. The relationships "must be visible to the world, so it shows we're not in competition with each other but different forms of the same reality," said United Methodist Bishop Boyd Grove, ecumenical officer for his denomination.
COCU served as a catalyst, Armentrout said, and churches that began dialogue continued it. COCU, now called Churches Uniting in Christ, has asked its nine denominations to begin working at the local and regional levels as much as possible.
Leaders hope by 2007 the nine will all have full communion agreements with each other, said Theodore Gill, Presbyterian ecumenical officer in Louisville, Ky. "It's a way of churches bridging the divide as well as being more effective," he said.
After the Second Vatican Council (1962-65), the Roman Catholic Church began dialogues internationally, and those talks continue with a wide variety of groups, among them the Eastern Orthodox, Episcopalians, Methodists and Lutherans.
Stumbling blocks in talks are wide: Catholics believe in the pope; Eastern Orthodox follow the ecumenical patriarch; Protestants eschew both. Ordination of women and whether communion is open to all also are roadblocks.
Another sticking point is the historic episcopate, or the belief among liturgical churches that their priests are symbolic descendants from Saint Peter in an unbroken line.
Even those in the historic episcopate don't agree on who's in that special club. The Eastern Orthodox believe they are but don't believe the Catholics are. The Catholics certainly believe they are, but they don't include Episcopalians, who believe they are in that line, Grove said. Some Lutherans are, others are not.
Methodists are another case. "We Methodists know we're not," Grove said, laughing.
Despite the continuing differences, growing closer appears to be the future course for Christendom's many streams.