According to the World Wildlife Fund, each of us needs about 2.5 acres of arable land to be sustained with needed food. Then we need to add another two acres or so – enough land to sustain the plants and animals that keep our ecosystem balanced and fertile. So, each of the 6.7 billion human beings requires, at minimum, 4.45 acres of fertile land.

But the math stopped working in the latter part of the previous century. The fact is, we’re using about 5.44 acres per person on average, which exceeds the carrying capacity of our planet. And these numbers are skewed by our disproportionate ecological footprint as Americans – we require over 23 acres per person to sustain us at the standard of living to which we have become accustomed.

Perhaps we can be forgiven for developing this unsustainable lifestyle because we didn’t know what we were doing. But now, as the information becomes available – and increasingly incontrovertible – we have a new responsbility and opportunity. And here is my firm belief: whatever the pleasures that come from living an unsustainable, and therefore unwise, life, the pleasures of living a wise and sustainable life will be far greater.

I was speaking on these topics recently, and a woman told me she wrote a note to her husband during my talk, saying something like, “You got me up at 7 a.m. to hear some guy make me feel guilty for being a successful American? Thanks a lot!” But she told me later, with some emotion, that by the end of the talk, she felt God had spoken to her. “The Holy Spirit washed over me,” she said. She was genuinely excited about the chance to learn to live better, and to seek a higher kind of success than we have achieved so far – a wise success, a good success, a sustainable success.

This is true in my own life. When I was researching my most recent book, I kept adding some small choices to my life to adjust my lifestyle to what I was learning. For example, we set a moratorium on incandescent bulbs in our house. Whenever one blows, we’re replacing it with a compact flourescent, and it feels fantastic to do so. I took about an hour and built a composting bin in my back yard, and it’s really enjoyable to add biodegradable kitchen scraps to it each day. These are small things, but I think if you try them, you’ll agree: this isn’t drudgery and painful sacrifice.

As the psalmist said, “You show me the path of life. In your presence is fullness of joy; in your right hand are pleasures forevermore.” I think it was Jane Goodall who said something like this: “You thought the age of reason was good? Wait until you see the age of love!” And I would add, “You thought the age of consumption and waste was good? Wait until you experience the joy of the age of sustainability and wise use!”

In Deuteronomy 15, God promised the people that if they lived according to the Lord’s ways, there would be enough for everyone and “there will be no one in need among you.” This is the dream: that we learn to live “in the ways of the Lord” so that there is enough for everyone and the planet is well-cared for, flourishing and green, full of birdsongs, and teeming with life, to the glory of God.

Brian McLaren’s new book is called Everything Must Change: Jesus, Global Crises, and a Revolution of Hope.