Jennifer Zickel and her two daughters, Emily, 4, and Natalie, 7, are not happy that their priest's decision to stop training girls to be altar servers. (Linda Davidson/THE WASHINGTON POST)

Mass had just begun at Corpus Christi Catholic Church when Jennifer Zickel, a Sunday school teacher, glanced at the church bulletin and saw something that made her sick to her stomach.

Tucked in with announcements about a new electronic donation system and a church dinner at Margarita’s Mexican restaurant was news that Zickel, the mother of two girls, had been dreading: Corpus Christi would no longer train girls to be altar servers.

Zickel burst into tears and ran to the bathroom.

“I knew right then that our family couldn’t stay at this church anymore,” Zickel said, her voice breaking. “I’m a mama bear, and they’re going after my girls.”

The decision last fall by Corpus Christi’s pastor, the Rev. Michael Taylor, and the response of Zickel and about a dozen other families who left the 1,100-family South Riding church reflect ongoing tensions among American Catholics over the role of women. About 50 families from across the country wrote letters of protest to the Arlington Catholic Diocese, and a vigil is scheduled for Sunday outside the diocese’s offices.

The subject has played out unusually in the diocese, which was the next-to-last in the country to say, in 2006, that girls were eligible to help priests at the altar. (The diocese in Lincoln, Neb., still has a boys­-only policy.) Arlington Bishop Paul Loverde left the decision up to individual priests. Five years later, about 60 percent of the diocese’s 68 parishes across northern and eastern Virginia still allow only altar boys, a diocese spokeswoman said.

Some share Taylor’s belief that the positions should be reserved for boys, who may become priests and help ease a major Catholic clergy shortage. Girls who had already trained as altar servers at Corpus Christi were allowed to continue, but they cannot wear the new black, priestlike robes the boys began wearing. People who oppose girl servers see the task as priest-like and note that the church teaches priests must be male because they model Jesus.

The Corpus Christi controversy highlights the sometimes-conflicting trends in contemporary Catholicism. The church is trying to hold on to its orthodox doctrine and firm worship structure while making room for cultural shifts, such as gender equality and a push by laypeople for more involvement in decision making.

For the most part, women are becoming more prominent in Catholic life. There are twice as many lay ministers — such as baptismal directors or school directors — as there are priests, and three-quarters are women. Women also increasingly serve in ritual roles during Mass, such as helping priests with Communionand doing readings.

But Catholic priests ultimately hold authority in their parishes and answer only to clergy above them, not to laypeople.

Taylor, who did not return phone calls for comment, wrote in the parish bulletin that he hoped the church would “create opportunities, and perhaps clubs” for girls as a way to help them find ways to serve the church, rather than serving at the altar. Loverde has not responded directly to requests by Zickel and others to meet, people on both sides said.

Caitlin Bootsma, the diocese’s spokeswoman, said she thinks the number of displeased parishioners is very small.

“The rest of the community either supports it or is getting used to it,” she said. In the diocese overall, “we don’t hear much on the issue at all anymore.”

After Taylor’s announcement, Zickel and her husband and two daughters, ages 4 and 7, stopped attending Corpus Christi. Zickel continued to teach at the Sunday school through June before the family started “floating around,” driving up to 45 minutes in an effort to find a parish with altar girls.

Mary Barnes choked up as she described watching her seventh-grade daughter serve during Mass in a white robe while the boys were switched to black ones. Barnes has attended Corpus Christi, in a booming area of eastern Loudoun County, for 13 years.

“It’s really hard to sit in church every weekend looking at that,” said Barnes, a manager at AOL. “It’s demoralizing, understanding you’re not really wanted.”

The Vatican in 1994 approved the participation of girls in altar serving, and the official Vatican newspaper has run pieces characterizing the acceptance of girls as correcting a “profound inequality.”

But Pope Benedict XVI and his predecessor, Pope John Paul II, have in general sided more often with traditionalists who fear watering down core Catholic teachings, such as that God sets separate roles for men and women.

In recent months, liberal Catholic publications have written about churches where girls are no longer being trained to be altar servers, saying the change reflects a turn to the past. The Phoenix diocese’s cathedral returned to boys-only altar servers this fall.

But debate over such subjects is less widespread than it was when the Vatican first allowed altar girls. While Washington’s archdiocese allowed female altar servers almost right away, Arlington’s decision not to caused more open debate than when Loverde approved female altar servers in 2006. Some experts on U.S. Catholicism say this is because many liberal Catholics have left the church in recent years.

Barnes has two younger daughters who, like Zickel’s, are too young to have been grandfathered in at Corpus Christi. Despite her opposition to Taylor’s decision, Barnes says she encourages her older daughter to keep serving, in part because “a lot of women” say they are grateful to see her performing tasks such as helping prepare the altar for Eucharist and carrying the cross during entrance and exit processions.

Asked whether she has considered leaving Corpus Christi, Barnes said: “Many other churches in the area also don’t allow altar girls. And I want to be glass-half-full, that if they see our perseverance, the attitudes will change.”