(RNS) The Rev. Michael Kinnamon, ordained in 1976 in the Christian Church (Disciples of Christ), is general secretary of the National Council of Churches. Formally organized in 1950, the NCC traces its roots back 100 years to the Federal Council of Churches, an earlier national effort to highlight Christian unity.

The NCC unites more than 100,000 local congregations from mainline Protestant, Orthodox, African American denominations and historic peace churches. When the NCC speaks out on issues including health care and immigration reform, it typically partners with Jewish, Muslim, Buddhist, Native American and other religious groups.

As Catholics, Protestants and Orthodox Christians mark the annual Week of Prayer for Christian Unity, Kinnamon talked about unity and the fragmentation of faith. His responses have been edited for length and clarity.

Q: How would you define the NCC’s approach to ecumenism?

A: Coming together around a common mission, to engage in dialogue and grow closer to one another, to be a reconciling witness in this culture.

Q: Do alternative expressions of faith — the emerging church or home churches — mean the end of mainline denominations?

A: I appreciate that there’s a lot of energy around new forms of church, but they themselves may move in the direction of offering a more structured witness. In the meantime, some of their vitality can help renew historic churches. We’d like to bring together different kinds of churches, share examples and renew each other.

Q: With such different expressions of faith and opposing views on so many issues, is Christian unity even possible?

A: There is no shortage of work to do and, yes, there’s fragmentation in the culture as well as in the church. We can either say, “Oh, gosh, unity is too hard,” or, “This is precisely the time to bear witness that God is a source of reconciliation that can hold us together despite our differences.”

I understand why some people roll their eyes at the mention of Christian unity. But the reality is that I speak to a range of churches, from Greek Orthodox to Quaker, and together they speak out on Afghanistan, health-care reform, gun control, the elimination of nuclear weapons. It’s astonishing. They do it because they recognize some degree of common faith, and they’re willing to bracket issues that have been divisive.

Q: Episcopalians and Lutherans are struggling to preserve their own unity despite disagreements on gay rights. Some say schism is inevitable. If a denomination can’t even agree amongst its own people, what hope is there for broader unity?

A: Mainline churches never were aligned around ideological sameness. Because of their common belief in Jesus Christ, liberals and conservatives were able to sit in the same pew. If we recognize a common allegiance to Jesus Christ, we can live with differences that threaten to rip society apart. One of the things I lament is we don’t have the wide-tent churches we used to have.

Q: Does it concern you that some Christians see community as a group of people who agree on particular issues?

A: Individualized spirituality that’s replacing the corporate church is problematic. The NCC attests to a faith that transcends like-minded enclaves and includes people who would otherwise avoid each other like the plague. What binds them is not what they have done, but what God has done. We don’t create the unity of the church. It is a gift we have received from God.

Q: Do you see any contemporary evidence that Christians are recognizing their unity?

A: The fundamental division between the Orthodox Church and Roman Catholics dates from the 11th century. But in our era, Catholic and Orthodox leaders have said there’s no reason for continuing this disagreement and we can see the way forward toward deeper unity.

Justification (how human beings achieve God’s grace and, thus, salvation) was the key issue of the Reformation, and now Lutherans, Catholics and Methodists say there’s no reason to maintain the divisions of the past.

I won’t pretend that ecumenism is always lived out, but there are ways we can stake steps forward, clear away some of those old divisions and make it possible to live together.

(Nancy Haught writes for The Oregonian in Portland, Ore.)