Dallas (ABP)—For the first time, advocates of the house-church movement in America have solid facts to back up their enthusiasm.

And those stats are shocking: Perhaps one in five American adults attends a house church at least once a month.

While attendees themselves have long said that an increasing number of Americans are moving from First Baptist on Main Street to living-room congregations, the very nature of home churches—decentralized, undocumented and unadvertised—has made them difficult to study. Until now.

In a June report from the Barna Group, evangelical researcher George Barna said 70 million Americans regularly attend or have “experimented with” a house church. That’s an increase of 8 percent since 1996, the report said. Moreover, the movement is taking on evidence of permanence, he said.

“The traditional ways of thinking about and experiencing ‘church’ are rapidly being revolutionized by a form of ‘religious choice,’ in which people are taking greater personal responsibility for their spiritual experience and development,” Barna said in the report.

“Today, house churches are moving from the appraisal phase into the acceptance phase. We anticipate house-church attendance during any given week to double in the coming decade and a growing proportion of house-church attenders to adopt the house church as their primary faith community.”

Furthermore, the study noted, more than 20 million adults attend services in home churches each week. Over the course of a month, that number rose to 43 million. Findings were based on a year of research including phone interviews with more than 5,000 adults.

House churches—also known as “organic churches,” “home groups” or “mosaics”—tend to be decentralized in structure, committed to forming in-depth relationships and patterned after first-century Christian fellowship—before church institutions, bureaucracies and denominations emerged.

Some emphasize spiritual experience over rational analysis, while others are led by ordained pastors with seminary degrees. Most are nondenominational and include roughly 20 people, kids included.

Although it has come into its own in America during the past decade, the house-church model of faith community is nothing new. During the 1970s, the United Kingdom experienced a rapid proliferation of house churches that later conglomerated into larger, more traditional church bodies. And in communist countries like China, Christians have used an underground home-church model for years. Experts estimate that 80 million Chinese Christians gather in homes each week.

Of course, for early Christians, home church was the only church. The original Christian churches depicted in the New Testament were small gatherings led by followers of Jesus.

Tony Dale, an Austin, Texas, physician and founder of House2House, a home-church network, said the New Testament teaching of Jesus is the very thing on which house churches depend. Jesus was the “antithesis” of modern church leadership, Dale said, in that He had no social position, no backing and no seminary degree. Jesus simply had “a darn good relationship with His Father,” Dale said.

New Testament Christian leaders were distinguished not by their seminary degrees but by showing kindness, he added.

Dale and his wife, Felicity, came to the United States from the United Kingdom in 1987. They got involved in house churches after their traditional church changed locations and their pastor encouraged them to begin a more organic movement.

House2House, a result of that move, encourages and supports home churches with a magazine, newsletters, books and a Web site. Dale is an unpaid member of the House2House board of directors. Felicity’s latest book, “An Army of Ordinary People,” was published in 2005. Together they host conferences and training seminars about home churches.

They also start churches in the Austin area and then “leave as quickly as possible.”

After they started leading home churches, Tony Dale said, he noticed certain intangibles in the smaller, more intimate format had faded away unnoticed as his “legacy” church grew. For him and many others, it’s the subtle things—like a spirit of community and the participation of everyone, regardless of station or age—that make the difference.

“Being a Christian has become a series of events,” Dale said. “Christianity has nothing to do with meetings; it’s about how we live. Jesus came that we might have life, not meetings.”

Dale’s sentiment echoes what other home-church proponents have said: The church model of the New Testament is a far cry from the traditional churches most American Christians attend today.

David Anderson, a former Presbyterian minister, said he had the same inclination when he “began to feel increasingly uneasy about the format of our services and the leadership structures, when compared to Scriptures.”

The meeting of believers in 1 Corinthians was “participatory,” Anderson said, in that several people spoke and others were encouraged to “judge the message. We were not doing that.”

Anderson runs the House Church Network and its Web site, housechurch.org, which serves as a directory and information board for other house churches. The site, which lists 1,193 house churches nationwide, started in 1992.

The 53-year-old father of six sees “many advantages to a plurality of elders all equal in their responsibilities.”

Anderson said his favorite part of the house-church model is its spontaneity in everything from teaching to the food people often bring to share after services. For the past 15 years, he has belonged to the same house church, which meets at a different house every Sunday.

“The appeal is joy of ministry (and) serving others in Jesus’ name,” Anderson said. “The appeal is that the form fits the function—function being the exercise of the (spiritual) gifts, equipping, ministry and priesthood of every saint.”

While methods differ from church to church, most house churches take the “priesthood of every saint” mandate seriously, allowing children to suggest worship songs and read from the Bible. In Anderson’s group, children stay with adults during the whole meeting, and all people participate in discussions of the text.

In most house churches, offerings go completely and directly to outreach and charity work, since meeting in homes translates into almost no operating costs. Often, house-church communion involves eating a full meal together, and baptisms happen in bathtubs, rivers and—in Dale’s case—a Jacuzzi.

The practice of baptism reveals another important tenet to the house church, one that some critics attack as a shortcoming—the absence of a single position of authority. In Dale’s group, for instance, whoever leads a convert to faith performs the baptism for the new believer. Sometimes that freedom means a two-day-old Christian baptizes another new Christian.

And with no pastor, house churches can fall victim to one dominating participant. As Anderson said, “The blessings of intimacy in a small group can actually become a curse if love doesn’t prevail at all times.”

An absence of leadership also concerns some who fear small groups of people could gradually depart from biblical truth and sound theology.

But many home-church proponents say God and the Bible are the only sources of authority necessary for church to happen. Movements that remain simple and “lay-led” will be better able to focus on the Bible, the thinking goes.

Home-group leaders also claim that, historically, heresy emerges as leadership becomes more formal, not when it springs from the grassroots.

Perhaps the greatest weakness a home church faces, Dale suggested, is the tendency to “turn in on itself.” House-church leaders must use their influence for “strong evangelistic” growth, he said. They must also watch for potentially manipulative personalities and lack of love in their midst, he said.

“There are lots of negatives” about house churches, Dale said, noting that “flaky” leadership and negativity can also hamper growth. But he added: “To be honest, that’s true in traditional churches as well. What we do see is that the Holy Spirit seems to be orchestrating some fascinating checks and balances (in the house-church model).”

Both supporters and critics agree home churches are growing in the United States. According to the Barna report, the people most likely to attend a house church are men, home-school families, residents of the West and minorities. Dale said Barna’s report also demonstrates the house-church movement is growing more diverse.

“It’s almost inconceivable to me that almost 9 percent of the population last week attended a home church,” Dale said. “This is huge. It’s obviously involving every type of background.”

More important perhaps, Barna says the growth is here to stay. When a movement maintains 15 percent market penetration for at least six years, Barna said, it qualifies as a cultural trend. If his estimates for monthly participation are accurate, house churches have reached that plateau. At that point, it becomes a permanent fixture in society, the report said.

No matter the roots or outcome of the trend, many house-church attendees say they bear no animosity toward the traditional churches they left behind. They look to them as a source of history and a foundation that can complement the trend.

“I am honored to be among Christians at any place or any time,” Anderson said. “I wish the home-church movement could be an influence for true unity. The church should return to apostolic hospitality, which means that where Christians are, other Christians are welcome too.”