If you've looked around at the state of our planet and been tempted to say, "God help us," you're not the only one.

From intentionally set fires burning across vast tracts of Indonesia's tropical forests to clear the land for agriculture, to high-level reports that our oceans are being rapidly scoured of fish and other marine resources, it should be obvious that we are setting ourselves up for a crisis of global proportions.

Some even argue that God got us into this mess to begin with. After all, we have done what the Good Book tells us. We have been "fruitful and multiplied" to such an extent that Earth's human population, which was a mere 3 billion in 1959, is now fast approaching 7 billion -- and will, by most estimates, top 9 billion by around 2042.

And we have "subdued the Earth" so effectively that our wild forests are being replaced with monoculture agriculture, our oceans are becoming deserted, and deserts worldwide are spreading at an alarming rate.

Clearly a bit of divine guidance wouldn't hurt at this point.

Of course, there are those who are itching to see the Apocalypse and the Rapture. But if you're among (what I pray is) the majority of humans who care about the planet and leaving it intact for future generations, then you probably already sense that the status quo is a dead end, literally. We cannot allow population and consumption of the Earth's resources to rise apace.

But who has the clout and credibility to leverage such change? Well, God, for one.

Increasingly the faithful are stepping into the arena of environmental activism, reports Gary T. Gardner, author of a recent book titled "Inspiring progress: Religions' Contributions to Sustainable Development" (W.W. Norton; 2006).

With environmental degradation continuing unchecked, Gardner asserts that only a fundamental change in how we view our planetary resources can prevent a global crisis. This will require a change in our society's definition of "progress" -- as well as a new economic paradigm, he says.

"Economics in the 20th century produced enormously productive but also highly polluting and resource-intensive industrial economies. That model, commonly called neoclassical economics, remains dominant today, and indeed is being pursued by developing economies seeking their shot at prosperity. But key elements of the neoclassical approach cannot be sustained," he warns.

Gardner is not yet in the majority. Pollyannaish adherents to the status quo still reassure us that new technologies, new resources, and human ingenuity will see us through if we just let science and corporations have a free rein and free markets.

Wouldn't it be lovely to think so.

But scientists themselves are not so blithely optimistic. Gardner cites Dennis Meadows, an American researcher whose computer models of global resource consumption have prompted considerable debate.

In a 2005 interview with Gardner, Meadows said: "What we find over and over again for the last three decades is that as long as you have exponential growth in population and industry, as long as those two embedded growth processes are churning away to produce larger and larger demands on the base, it doesn't make any difference what you assume about technology, about resources, about productivity. Eventually you reach the limits, overshoot and collapse . . . Even if you make heroic assumptions about technology and resources it only postpones collapse by a decade or so. It's getting harder and harder to imagine a set of assumptions that allow the model to produce a sustainable result."

In other words, we've got one planet, finite resources -- and more and more people consuming more and more resources every day. Eventually, something has to give.

Ideally, though, before something does give, human society must embrace "sustainable development" -- whose oft-quoted definition, as presented in the landmark 1987 report by the United Nations' World Commission on Environment and Development, is: "Development that meets the needs of the present without compromising the ability of future generations to meet their own needs."

As Gardner points out, this will require governments and policymakers worldwide to recognize that "all economic activity is rooted in the natural environment, and is deeply dependent on it."

Until now, the prevailing consensus has been that governments should pursue rapid economic growth first, then clean up the mess they've made second.

Despite the fact that today's developed nations have had the luxury of this approach, none has achieved sustainability. And with world population now more than twice what it was less than five decades decades ago, the margin for error is rapidly narrowing.

Other countries will have to get development right the first time. That's especially the case for China and India, with over a billion mouths to feed each. And with each of those people demanding clean water and shelter, as well as dishwashers, computers and cars, there will be no easy second chances.

Once forests have been cleared for agriculture, deserts have encroached on farmland, and waters have been polluted and overfished, options for introducing sustainable policies are dramatically limited.

Therefore, as Gardner points out, over the next few decades we will have to move our environment from the periphery of our political and social concerns to the very center. And, crucially, we will have to restructure our economic system to reflect this priority.

In the process we will have to adopt a new understanding of what "wealth" and "quality of life" mean. This is where religions and faith-based communities, with their focus on non-material and spiritual fulfillment, can offer us guiding values.

Gardner cites a Buddhist village-development movement in Sri Lanka, called Sarvodaya Shramadana, that embraces a vision of well-being based on 10 basic human needs: A clean and beautiful environment; a clean and adequate supply of water; basic clothing; a balanced diet; a simple house to live in; basic health care; simple communications facilities; basic energy requirements; well-rounded education; and cultural and spiritual sustenance.

This may sound Spartan to those of us in the developed world; but for the majority of our fellow human beings who have far less -- and the many millions who have nothing at all -- such a community would be a godsend.

In fact, many in nations of the developed world, too, would be delighted to have such security and well-being, since one reality of a finite planet and a burgeoning human population is inequality. It will never be possible for each human being to receive an equal share of available resources.

Still it is eminently possible, and now critical, for the developed world to produce more carefully and consume less greedily so that the rest of the world can have a fairer share of the planet. The developing world, too, must do the same.

But with time getting short, and governments making very little real progress toward sustainability, religious leaders may be our best bet for reaching the multitudes: 85 percent of the world's people are religious adherents, with 30 percent Christian, 20 percent Muslim and 15 percent Hindu, according to Gardner.

And no new doctrine is needed. In principle, every religion condemns killing and stealing, and degradation of our environment is both; the taking of life and stealing from future generations.

In 1985, after the 18th space shuttle mission -- the fifth aboard Discovery -- returned to Earth, one of its crew, the Saudi astronaut Sultan bin Salman al-Saud, talked about the crew's changed worldview. "The first day we all pointed to our countries. The third or fourth day we were pointing to our continents. By the fifth day we were aware of only one Earth."

Floating in the infinite vastness of space there is only one Earth. It is a miracle of life and, though we did not create it, we are its custodians. Our reverence can save it -- just as our greed can destroy it.

Ultimately, whatever our religion (or not), we share the same place of worship. Our neighbor's plight is our own, and their well-being is inextricably intertwined with ours. That truth is one we can all have faith in.