Be like the wise man who built his house on the rock.

In Papago Park, a preserve near the center of Phoenix, two small rock mountains rise up from the desert. One of them, Garden Butte, is 1.6 billion years old. The other, about half a mile away, is a youngster at only 17 million years old.

Because Phoenix receives fewer than ten inches of rainfall every year, Garden Butte and its younger cousin aren’t covered with trees. One sees only rock, rock that has been around for eons. When I travel to the United Church of Christ conference office, or to see friends, I try to get to Papago Park to see those two rock mountains. Being in the presence of something millions of years old helps me keep my life and my ministry in perspective.

There’s Camelback to the north, the Estrellas on the west and the Superstitions to the east. South Mountain Park, where I spent a good part of my childhood exploring and scrambling over boulders, completes the circle. If it’s not smoggy, you can see beyond the Phoenix mountains to others in the distance, sometimes even as far as Four Peaks, which may be crested with snow if it’s been a wet winter.

As I gaze at these peaks, I sometimes imagine them emerging from the desert floor. I see dinosaurs roaming the land. I wonder which layers of rock color and variety represent which layer of earth’s history. The scope of time reminds me that “a thousand ages in thy sight are like an evening gone.”

“Build your house on the rock and not on the sand.” When Jesus ended his sermon with these words about faith, he was probably standing on a mount not unlike these Phoenix mountains. Matthew says the crowd was astonished, for Jesus “taught as one who had authority.” That’s not surprising. Whether in Israel or Arizona, any desert dweller knows you build on rock and not sand. Just look at what survives in this land. It’s not tumbleweeds, that grow fast and big in easy places like sandy washes, but then dry out between the rains and blow away in the first big wind.

It’s the saguaro cacti, “giants of the desert,” 70-feet high with root spans to match, that make it to two centuries. In the high desert of Santa Fe (altitude 7,000 feet), pinons and junipers survive too. They put down roots in the rockiest of places, wherever they have something to hang onto. A favorite painting by a Navajo friend shows a lone pinon tree growing out of the side of a cliff, its roots anchored in the rock. It’s not a huge tree, but it’s there, a good metaphor for life and ministry in the desert.

Desert people also know about desert thunderstorms, another part of Jesus’ sermon. For years, developers in the Southwest have sold newcomers land in the flood plains. It’s cheap to build on sand, and people can’t believe it ever rains here. But it does. Clouds move in and out in minutes, leaving the sightseer drenched. Those newcomer houses built on the sand are the first to go. What lasts in the desert are the “rocks of ages” and the life, both human and plant, that are anchored in them.

As a child I thought the mountains would always be here, always offering a place to climb and explore, always inviting me to imagine other worlds in long-ago times, connecting me to the eternal. The desert and its mountains gave me the foundation I needed to get through the storms and dry times of life. When I moved back West 18 years ago, I found new sermons and lessons in the landscape around me.

But in much of the West, neither children nor adults have a chance to know the desert’s incarnation of the Christian faith. Every hour an acre of desert is taken for development. Since 1990 the Phoenix area has doubled. Albuquerque and Las Vegas are not far behind. The exponential growth has drastically changed life not only for plants and animals but also for people. More and more shopping malls, big-box stores and housing developments block the vast vistas and mountain views. In Phoenix, air pollution often dims the valley’s mountains. Hundreds of miles away, the colors of the Grand Canyon—layers of red and gold rock millions of years in the making—are often obscured by smog from the cars of Phoenix, Vegas and even Los Angeles.

The rapacious development of the West troubles me. It’s not just nostalgia for days gone by, or the environmental concerns. When ageless mountains are blocked by Wal-marts and smog, we don’t just lose breathtaking views. We also lose a direct experience of Jesus’ rock foundation. When green lawns and swimming pools replace centuries-old saguaros or pinons, plants and animals aren’t the only losers. We’re also destroying our incarnate connection to Jesus’ lesson on building a faith that lasts.

Ironically, the overdevelopment also illustrates Jesus’ warning about false foundations. Like a house on sand, the West has an equally risky base—borrowed water. Depleting water tables and pumping water from faraway sources like the Colorado River has made development fast and easy. But a region built on borrowed water has no more chance of surviving than a house built on sand.

I am grateful for the foundation of faith laid for me by both the Bible and by this desert land. As a minister of a young church in the Southwest, I believe my call is to pass on that biblical bedrock and also to care for this corner of creation that makes it incarnate.