TORONTO (BP) -- Nearly a century ago, my grandfather's family, a large brood of tall, thin Norwegian immigrants, settled in rural South Dakota. With the promise of fertile land of their own, they, among thousands of others, migrated north to become "homesteaders" in the fertile plains of Saskatchewan.

In less than 30 years, Saskatchewan's population swelled more than 10 times -- from 90,000 in 1901 to 920,000 in 1930. Scores of families packed in Model T Fords hobbled their way down the dirt trails to find their new lives, breaking ground and planting crops in rich virgin soil. Saskatchewan, like most of North America, was largely rural.

But things have changed. We have urbanized.

Even though the total population of my home province has not significantly increased since 1930, its concentration definitely has -- it too has become increasingly urban. As the last bastion of rural utopia in the minds of many, it is now considered to be more than 65 percent urban. Tucked into their subcompact cars, former farmers have migrated to the cities to provide for their families. Today's farmers are far fewer, and their farms are much larger.

From where Model Ts once migrated out, Honda Civics are now coursing back in. More than 82 percent of North America's people now live in cities, and the numbers continue to climb at a disquieting rate. The Mayberry we had once known and enjoyed is becoming a nostalgic memory.

Historically, evangelicalism kept up to rapid rural population trends through an inventive and necessary institution called the bivocational planter-pastor. These were iron men who farmed their own land, raised their families and sensed an overwhelming call of God on their lives to bring Good News to their neighbors.

Through the integrity of their own testimony and reputation, they formed congregations in schoolhouses, farmhouses and barns. These humble leaders did not consider themselves clerics or religious professionals -- just servants and stewards of history's Greatest News. Armed with this Gospel, they planted church upon church and changed the social-spiritual landscape of North America. My great-grandfather, Christian John Christopherson, was among their number.

Today, we find ourselves in a similar moment of history. Migration patterns have led to the majority of North America's populace living in highly concentrated groupings of ethnically diverse peoples. What once existed as an anomaly isolated in Manhattan has become our social norm. A single building holds more residents than the Mayberry many of us once called home. A sea of similar buildings surrounds this building. Cranes interrupt the skyline with the incessant construction of new high-rise buildings designed to house the burgeoning populace requiring a place to call home.

As the super-density of population increases, many of our church planting and evangelism models lose their effectiveness. The Manhattanization of North America requires a new strategy and a new kind of church planter -- an iron man of a new order -- one who works in the city, raises his family in the city and, with the integrity of his testimony and a clear call from King Jesus, brings Good News to the city.

Where will we find these iron men?

Fortunately for us, King Jesus has already been calling them. These heroes are resident in our cities and humbly, obediently are giving themselves away for the sake of the Gospel. Without fanfare they have opened their apartments, boardrooms, local libraries and factory break rooms so that their neighbors and co-workers can experience a God of love.

Are you one of them? Let us know. Let me know. If we are going to reach our communities with the Gospel in the places where the world is moving, bivocational pastor-planters will create the agile and effective mission force required for this sustainable work.

The Manhattanization of Mayberry requires these leaders.

If you believe God is calling you to bivocational church planting, please explore namb.net/mobilize-me. We want to help you.

If you are already a bivocational pastor, the North American Mission Board has resources to support and encourage your faithful service. Learn more at namb.net/bivocational-pastors.

Jeff Christopherson (@Christopherson3) is a missiologist, church planting strategist and NAMB's vice president for Canada and the Northeast regions. Get Baptist Press headlines and breaking news on Twitter (@BaptistPress), Facebook (Facebook.com/BaptistPress) and in your email (baptistpress.com/SubscribeBP.asp).

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