[Note: This is a followup to an earlier post on why I believe every Christian should care about the environment.]

The earth is God’s temple. A growing number of evangelicals accept the importance of “creation care.” So why don’t more of us care about climate change? According to one survey, only a third of Christians say climate change prevention is an important part of our responsibility to steward the earth (though a majority say it’s important for other reasons).

Put another way: Why are Christians, particularly evangelicals, more skeptical about climate change than the general population?

Humanitarian organizations like World Vision (my former employer) see climate change as one of the biggest threats to the poor and vulnerable in the developing world. Even the US military, hardly a haven for liberal thought, recognizes climate change as the most significant threat to our national security.

So why do we who are Christian have such a hard time seeing what they see?

For those who remain skeptical about the causes and implications of climate change, I’d like to pose a pair of questions that Rich Stearns shared with employees of World Vision when I was there:

1. What’s the worst that could happen if we respond aggressively to climate change, only to learn in hindsight that our concerns were overblown?

The answer: Collectively, we might wind up a few hundred billion dollars poorer. That’s the equivalent of 1-2% of ONE YEAR’S global GDP.

Some of that would be money well spent — even if climate change turned out to be more of a whimper than a roar. For example, with a finite supply fossil fuels (no matter how much we “drill, baby, drill”), do any of us really believe we shouldn’t invest in alternative energy sources?

2. What’s the worst that could happen if we do nothing, only to learn that human-induced climate change and its effects are real — and every bit as serious as we’ve been told?

Let’s start by putting it in crass economic terms. Failing to rein in greenhouse gases could cost up to 20% of global GDP. (And you thought the last recession was bad.)

More important is the human impact. No surprise, it’s the desperately poor — those who have contributed the least to climate change — who stand to suffer the most. In fact, they’re already feeling the effects of climate change. From the increasing frequency and intensity of droughts in parts of Africa, to rising sea levels already threatening to overwhelm an entire nation.

Two decades of progress combating extreme poverty could be wiped out if we fail address climate change.

That’s our choice: Spend a few hundred billion dollars now or lose trillions later — and jeopardize millions of lives.

Still, many doubt the science behind climate change, even though the underlying principle, the greenhouse effect, has been a proven scientific fact for well over a hundred years. But why? What’s the motivation for all this skepticism?

Could it be that those of us in the top 2% simply don’t want to give up the standard of living to which we’ve grown accustomed? Could it be that we’re happy to go on using the earth as we see fit and leave the mess for someone else to clean up?

As Christians, we will have a hard time reconciling this attitude with the biblical reality that the earth is not ours — that it is not first and foremost our dwelling, but God’s.

What will we say when the time comes to give an account for how we’ve tended God’s temple?