Two dozen real estate agents, developers and the tire-kicking curious filed into Holy Innocents Church on a recent weekday. They were not there to pray.

Milling about and poking around, they envisioned what the possibilities might be after the recessional hymn had rung through the cavernous sanctuary for the last time.

"I have a client who's interested in turning this into a jazz and blues club," said Jerry Summers, a Re/Max broker, pausing to admire the towering blue-and-green stained-glass windows that flank the 9,800-square-foot sanctuary.

Not even prayer will save Holy Innocents, in south St. Louis, and 18 other churches -- one built in 1860 -- that have been put up for sale block by the Roman Catholic Archdiocese of St. Louis. The sale involves 80 parcels of property -- schools, rectories, convents and churches.

This is business, and a painful business at that.

The heavy, wooden doors on all those churches closed yesterday, and buildings that in many cases were the spiritual and communal anchors of ethnic neighborhoods in this old Catholic city face a decidedly secular future, and perhaps the wrecking ball. The buildings, carrying a combined asking price of $30 million, are being sold separately and may eventually reopen as loft apartments, restaurants, theaters, clubs, museums and, in some cases, churches of other denominations.

The fit, at least in the short term, promises to be awkward.

Catholic churches, especially those in aging industrial cities, have been closing for decades as the urban faithful flock to the suburbs and the growth of U.S. Catholicism levels off. But the pace of closures is quickening, and for different reasons.

Seventeen Toledo area parishes were scheduled to close yesterday because they no longer can support themselves. The financially troubled Boston archdiocese is selling more than 60 churches to help pay for sexual-abuse claims. In Canada, a Catholic diocese in Newfoundland last month announced plans to sell all its churches and missions to help pay for a legal settlement stemming from actions of a pedophile priest.

The St. Louis archdiocese, which has closed 36 parishes since 1990, says the proposed sale involving 10 percent of its parishes is not tied to sexual abuse cases but is designed to strengthen the financial health of individual parishes, which are responsible for the operations of churches, schools and convents. The sale's proceeds will go to the parishes that will absorb the dwindling membership of the shuttered churches.

"For us this is regional planning. . . . We don't have the luxury of tiny parishes serving a few people," said Thomas Richter, the director of building and real estate for the diocese. "The worst thing that could happen is if [churches] just sit there like dead elephants in a neighborhood. We don't want parishioners to be ashamed of them."

In a city where Catholic roots predate the 1803 Louisiana Purchase and where Catholics identified their tightly knit neighborhoods by their parish, the transition is a painful end to a treasured way of life for people such as Dolores Roesch, who has spent all of her 64 years living in the shadow of the twin-steepled St. Boniface Church.

After World War I, many German street names here were Anglicized, but the industrious culture and tradition of this working-class German neighborhood lived on.

Taverns, hardware stores, restaurants and corner groceries have been leaving city neighborhoods for years. But in the Carondelet neighborhood, the 145-year-old St. Boniface, named for the patron saint of Germany, has been a constant in the face of dramatic economic change. Two parishes have closed and been folded into St. Boniface since 1932. Now St. Boniface, whose congregation has shrunk nearly 30 percent in the past 10 years, will close its doors.

"My grandparents built their house here 102 years ago because they wanted to walk to church," said Roesch, who now lives in the well-tended brick home with striped, green-and-white window awnings. "Any funeral, any wedding, you had to be there to sing. It was what you did."

That was life in Carondelet, a life in the past tense. Now two-thirds of St. Boniface's congregation are senior citizens. The Rev. James Gray, the white-bearded priest who closed a parish in Detroit before coming to St. Boniface, has sensed the future since he came here in 2001.

"You don't hear babies crying in this church," he observed.

The archdiocese believes some churches will sell more easily than others. Richter, the archdiocese's real estate director, said newer and more easily adapted churches and recently built rectories and schools likely will be bought by other religious denominations or, in the case of the closed Catholic schools, charter schools.

Richter, a former developer, said the target client always is another faith, but the diocese has to be open to other, nontraditional uses.

"I don't know that the archbishop would say it this way, but what used to be the house of God can now be the house of Joe," Richter said.

Attorneys are writing restrictions into sale agreements to ensure what Richter calls "nonsordid" use -- no houses of devil worship, no abortion clinics, no strip clubs or activities that would be in direct conflict with the church.

Overtly religious objects already have been pulled out of some churches in preparation for the changeover. Stained glass with clear religious symbols will be removed if the church is converted to another use.

The iron cross was removed recently from the steeple at the 107-year-old Holy Family Church, a south side institution once dominated by city employees and Anheuser-Busch workers.

"When that cross came down, it was like the church was in its underwear. The dignity was gone," said the Rev. Rickey Valleroy, an energetic former bartender who believed he had saved the parish on the strength of Friday night fish fries and recent packed houses -- a doubling of church attendance.

"I used to walk the neighborhood and dream of what the neighborhood was and whether it can be again," Valleroy said.

The church held an auction on a recent Friday night for parishioners who had expressed an interest in owning a piece of the church's life -- a rock from the foundation, a meat grinder from the kitchen, wine glasses, a dozen crucifixes, some candleholders. The proceeds will go toward severance payments for school employees.

Valleroy said he is not troubled by Holy Family becoming loft apartments, if that is its fate. "It's no longer a church anymore," he said.

Although real estate agents, developers and financiers ultimately decide what the churches will be, those who grew up in them will deal with what no longer will be.

Linda Smith, who lives a block from St. Boniface, where her four daughters were baptized, said she will miss the ringing of the three 19th-century bells atop the church. Smith runs the old Carondelet Bakery with her husband, Bob, and hopes to continue seeing the comforting vision of rainbows above the church after spring and summer showers.

"This is a neighborhood on the verge of rebirth," Smith said. "If [closing] means St. Boniface is condos or an old folks' home, that's fine. I'd rather have that for the memories than to see it be torn down."

The Rev. Rickey Valleroy takes his turn at the buffet before an auction at Holy Family Church. The 107-year-old St. Louis church closed this week.

Organist Dorris Schmidt arranges her music before Mass at St. Boniface Catholic Church.Ravi Rao, 7, joined a protest in Boston after a string of planned parish closures prompted closure of his school ahead of schedule. Similar sit-ins have prevented some closures.Our Lady of Mercy Church in Newfoundland, Canada, also faces closure.