"We're doing service rather than having one," Hogland said.
Activities will include construction of a shelter at a homeless camp, cleanup at a nature center, improvements to an elderly man's house, corsage-making at a nursing home, and Habitat for Humanity home construction.
Most participants will work around Lower Bucks, but some will travel to Trenton or Philadelphia. A few will even pick up fallen apples, to be donated to food pantries.
Hogland said he doesn't know how many volunteers from the churches will turn out, but last year's Living Outside the Box - solely a Woodside Presbyterian event - drew 300 of its 625 members.
Participants were so enthusiastic, Hogland said, that they decided to do it again this year and invited all of the local Christian houses of worship to join in. They are Anchor Presbyterian in Newtown; Northampton Presbyterian in Holland; United Christian Church in Levittown; and Yardley United Methodist. St. Ignatius Roman Catholic Church in Yardley is not canceling Masses, but some parishioners are participating.
"The idea is that the [church] building is the box," Hogland said. "Our feeling is that Jesus wants us to live our faith outside the building."
The day's playful slogans ("Inside Out" and "The Church Has Left the Building") mask a serious question about whether the traditional way of "doing church" - gathering in pews for prayer, song, and sermon - will endure. Hogland noted that some national surveys report that today's young adults are less inclined to identify with religious denominations or join congregations.
"By some key measures, Americans ages 18 to 29 are considerably less religious than older Americans," the Pew Forum on Religion and Public Life reported last year.
One in four members of the millennial generation (born after 1980) are "unaffiliated with any particular faith," according to Pew, and are "significantly more unaffiliated" than were the previous Generation X and the baby boomers at the same age.
"Young adults also attend religious services less often than older Americans today," Pew researchers wrote in their "Religion Among the Millennials" report. "Compared with their elders today, fewer young people say that religion is very important in their lives."
How this trend might affect congregations and denominations in the decades ahead is hard to predict, says Alan Cooperman, the Pew Forum's associate director for research.
Despite all the evidence of religious disaffiliation, the survey also shows that millennials who belong to a church or identify with a denomination attend religious services at about the same rates their elders did at this age.
"We're not seeing that [sabbath] worship is losing its appeal," Cooperman said. "And we're not seeing that daily prayer is less among young Americans than it was among their elders at this point in the life cycle. So it's a complicated picture."
Living Outside the Box Sunday is not an attempt to boost membership in his congregation, according to Hogland. "Building the institution is not a winning strategy these days," he said.
The congregation of the future might have several worship sites - some in rented storefronts - rather than one central building, he said, with committees running projects and doing good without central supervision.
"These are the ways in which Christians convened in the earliest days of the church," he said. "They met in homes, or in secret. Church doesn't have to be tied to a building."
Contact staff writer David O'Reilly at 215-854-5723 or email@example.com.