As a boy growing up on the prairies of North Dakota, I used to look through encyclopedias and geography books for any mention of my state. Under the headings of other states and countries I'd see breathtaking pictures of snow-capped mountains, city skylines, and oceans. Under North Dakota, by contrast, I'd find a very short article and photos of wheat fields, cows, and grain elevators—all things I could see out my classroom window. They just didn't compare to Disneyland, Mount Rushmore, Old Faithful, the Empire State Building, or the Golden Gate Bridge.

Many people belonging to small churches feel the same way about the significance of their congregations. They wonder if anyone realizes that the heart of God is still beating in thousands of little congregations in every city, suburb, village, and county in our nation. Does anyone even know they exist?

As I read through clergy journals or review new education programs that tumble down from the denominational and parachurch hierarchy, I find good reason for this self-doubting. Even though most churches are small—roughly half of all churches have fewer than 200 members, and about two-thirds have fewer than 300—most church resources are designed for the bigger churches. Journals for pastors present rich resources to help the youth minister run a jet-hot program. But most churches don't have a youth pastor—or even a skillful, trustworthy, highly motivated layperson. There are articles on how to set up committees for music and worship and how to divide your church into small groups. But many congregations are small groups.

Large Protestant congregations are a relatively recent phenomenon in North America. At the time of the Civil War, the average congregation ...