What color is your church? I’m not talking about a multi-cultural congregation; I’m talking about political and social bents. Can your church be categorized the same way political commentators label the United States: either "red" or "blue?" Or is your church the center of a Venn diagram of liberal and conservative concerns? Is it purple?

Diana Butler Bass is the author of the new book "Christianity for the Rest of Us: How the Neighborhood Church is Transforming the Faith," in which she used a three-year study to discover the essence of the health of that all-too-rare animal—the vital mainline church. One key ingredient Bass noted was the blending of differing politics and social concerns (red and blue making purple) among congregations representing healthy mainline churches.

Rather than a centrist position, the purple color in these churches comes from congregants who side with one party or the other on various issues but who are altogether politically unpredictable.

"Given the issues and candidates in any particular campaign, following Jesus may take different forms at different times, involving a host of policy solutions, and balancing elements of each political party in a ‘lesser of two evils’ voting strategy," Butler Bass wrote on the God’s Politics blog this month.

"For purple people know that God’s reign judges politics, that voting is an act of Christian discernment, and that theology should critique policy. No earthly political party speaks spiritual truth," she wrote.

If churches are simply places where like-minded people can come together and feel secure among others who embrace the same political, social and community issues, they have lost some of the grace of Christian theology, according to the Rev. Gary Erdos, pastor of St. Mark Evangelical Lutheran Church in Yorktown, Virginia. He told USA Today recently that "God is calling us to something bigger than just our political views."

Differing political and social views may be easier to accommodate within one congregation than, say, differing theologies. But even on that issue there is wiggle room. In fact it may be essential if a church is to thrive.

According to Rick Atchley, senior minister of the Richland Hills Church of Christ in North Richland Hills, Tex., theological diversity is the secret to church growth.

"I’ve got people in my church who believe the Holy Spirit only operates in the Bible, and I’ve got people in my church that in their closets at home pray in tongues. I’ve got people in my church who are across the board on the role of women, on marriage and divorce, and on Jesus’ return," Atchley told church leaders gathered at the North American Christian Convention in Louisville earlier this year. Despite those differences, Richland Hills has grown into a mega church.

Atchley said unity in a congregation does not come from homogeneity. Rather, it comes through: 1) recognition of varying biblical interpretations, 2) differentiating Christian faith from cultural additions, and 3) separating doctrine from opinion. Atchley offers 10 practical ways churches can keep the peace despite differences among believers.

"Most churches split over subjective rather than objective issues," Atchley said. "It isn’t the question of the deity of Christ that splits churches; it’s personal faith issues."

In a bigger Church picture, Bass professes being tired of "religious right" and "religious left" categorizations dividing Christians and pigeon-holing committed believers into parties and positions that don’t fully reflect Jesus Christ. I don’t blame her. I’m tired of fearing that my friend won’t like my church because her politics differ from my senior minister’s. I’m tired of my church’s programs catering only to certain segments of society. I’m tired of people using religion as politics.

That’s why a purple church seems so much more biblical. There is room there for all who have sinned. Just as Jesus’ disciples represented a cross-section of society, so should our churches.

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