The greening of religion, although long overdue, is really a quite natural phenomenon. The texts of many faiths, indeed most, at some point reference the stewardship of this earth. More surprising is that today, secular environmental groups are seizing the opportunity to reach out to faith communities.

A Sierra Club report highlights faith-based environmental initiatives in all 50 states "spiritually motivated grassroots efforts to protect the planet." One line leaps off the page: "Lasting social change rarely takes place without the active engagement of communities of faith." Indeed. Think of the U.S. civil rights movement, Solidarity in Poland and the anti-apartheid movement in South Africa. Social change does not stick without the glue of religion.

But as these two movements one based on the love of God, the other on the love of the earth intersect, we should celebrate the initiative while remaining aware of the challenges and inevitable spats that await this quite remarkable marriage.

For centuries, the biblical command to "have dominion" over the earth was seen as a divine endorsement of environmental exploitation. But a radical shift has occurred, and most people of faith now support efforts to be good stewards of natural resources.

The Pew Forum's Religious Landscape Survey, released earlier this year, revealed widespread support for stricter environmental laws and regulations among Jews (77%), Buddhists (75%), Muslims (69%) and Hindus (67%), as well as members of mainline Protestant churches (64%), Catholic churches (60%) and evangelical ones (54%).

"Creation care" is the growing movement that has become a rallying cry among religious people who are concerned about the earth. In just the past few years, this nation has witnessed an explosion of environmental activity at the grass-roots level.

"We now have 5,000 congregations that are responding to climate change by cutting carbon emissions," says Gretchen Killion of Interfaith Power and Light, a San Francisco-based group active in 28 states. It helps churches and religious organizations lower their energy consumption. "Many of our members have installed solar panels, and three or four even have geothermal," Killion says.

The world needs this broad-based, interfaith movement one that offers practical environmental benefits and draws together people of diverse theologies. Catholics are working with Native Americans to preserve land and water; Muslims are making links between urban communities and sustainable farms; and Protestant churches are joining interfaith coalitions and "greening" their congregations by modifying buildings, installing compact fluorescent lamps, using conservation landscaping and purchasing organic, fair-trade coffee.

Though religions are sometimes scorned for dividing people and illuminating differences, the unifying goal of preserving the planet could do just the opposite: bring people of faiths together. Creation care can be "a great bridge-builder between evangelicals and mainline Christians," says Richard Cizik of the National Association of Evangelicals. Although evangelicals have traditionally distrusted environmentalists, who tend to be political liberals, stewardship of the earth is not a left-wing concept. After all, observes Cizik, "Aren't conservatives supposed to be conservers?"