Bells tolled at houses of worship across the country Friday morning — including most prominently at the Washington National Cathedral and Basilica of the National Shrine of the Immaculate Conception — in memory of those who died tragically in Newtown, Conn., last week.

To some faith groups, the ritual was a time to sorrowfully remember and pray for the 26 children and school staff members who died in the school shooting, as well as, in some cases, the troubled shooter who killed his mother and himself.

But to others, the ringing of the bells served as a call to political activism, primarily to limit the availability of guns and ammunition and to expand access to mental-health care.

“Remember the 28 who died in Newtown,” prayed the Rt. Rev. Mariann Edgar Budde, bishop of the Episcopal Diocese of Washington at the National Cathedral, where an interfaith group of religious leaders held a news conference Friday to call for moral leadership in response to the massacre.

“We will never forget, Lord God, and we pledge to honor their memory by doing what we all know is right,” Budde said, reiterating pledges to reform gun legislation and cultural attitudes toward violence.

Bells tolled for each of the victims of the Newtown massacre at the Basilica of the National Shrine of the Immaculate Conception in Northeast Washington. Bells tolled for victims all over the country on Friday. Monsignor Walter Rossi talks about the significance of the bells. (Hamil Harris/The Washington Post)

With bowed heads, the coalition of 20 leaders huddled solemnly together behind a microphone as the bells rang at the cathedral and nearby churches. Among them were Rabbi David Saperstein, who directs the Reform Jewish movement’s Religious Action Center; and Imam Mohamed Magid, executive director of the All Dulles Area Muslim Society, a progressive mega mosque in Northern Virginia; and the Rev. Carroll Baltimore, first vice president of the Progressive National Baptist Convention.

Rajwant Singh, chairman of the Sikh Council on Religion and Education, expressed his support for the cause at the gathering, adding that it has been four months since the shooting at a Wisconsin Sikh temple where seven people, including the gunman, were killed.

“Those bullets that hit Sandy Hook have hit the Sikh community again,” said Singh, who wore a green turban to commemorate those lost at Sandy Hook Elementary School.

He said that people who are moved to action should “continue to raise their voices to stop this violence.”

Some experts this week noted that another key issue on faith leaders’ agenda is a push to limit violence in popular culture, including movies and television shows, a topic that has long been close to the heart of traditional evangelical advocates.

The call to action has included both conservative and liberal voices.

The Rev. Richard Cizik, president of the New Evangelical Partnership for the Common Good, said at the cathedral press conference that there needs to be a change in the gun culture embraced by some conservative Christian leaders and politicians.

“We need a conversion,” he said. “American evangelicals need to be born again on this issue. . . . The power of these weapons and the bullets that ripped into every child and adult that were there should haunt us.”

Meanwhile, liberal faith leaders who have struggled in recent years to inspire the level of activism of conservative Christianity see an opportunity after the Newtown shootings and President Obama’s reelection.

Budde and the Very Rev. Gary Hall, dean of the National Cathedral, were among the most outspoken religious leaders to organize around specific measures after the shootings. Budde on Thursday sent a letter to all the parishes in her diocese saying that she felt “a new Spirit blowing in our land. . . . I am convinced that we are at an opportune moment to fundamentally change the course of our nation.”

The letter asked the parishes across Washington and suburban Maryland to ring bells Friday and to organize for a ban on semiautomatic weapons and large rounds of ammunition, tighter controls on gun sales, improved mental-health care and a “critical look” at glorifying violence.

Participants in the interfaith press conference echoed the sentiment, adding that they are mobilizing their communities to lobby Capitol Hill lawmakers and to develop anti-violence programs for schools and support initiatives to reduce illegal gun ownership, as well as gun buyback efforts. The National Council of Churches has declared Jan. 6 “Gun Violence Prevention Sunday.”

Budde and Hall are both relatively new to Washington and are expected to bring a higher-profile to the cathedral’s policy activism. Budde came last fall, and Hall came this fall.

The national Episcopal Church also this week called for members across the country to organize. It asked churches to pray and plan around the annual Feast of the Holy Innocents on Dec. 28.

When a reporter asked why Newtown has seemed to galvanize a wave of religious activism, retired Cardinal Theodore E. McCarrick said Friday that other shootings have affected many who sought to change gun laws and the culture, but that “you get to a moment you can’t take it anymore. We’ve got to restate our values.”

At the Basilica of the National Shrine of the Immaculate Conception, the largest Catholic Church in North America, Robert Grogan tolled the largest bell of its 56-bell carillon 26 times on Friday in remembrance of the slain students and staff members at Sandy Hook Elementary School.

“As I was tolling the bells 26 times, I thought about the 26 individuals and the enormity of what happened,” Grogan said, tears welling in his eyes.

“Throughout history, bells have been a summons in time of tragedy, a summons in times of victory, a summons in times of sadness and a summons in times of joy,” said the Very Rev. Walter R. Rossi, rector of the Basilica.

Michelle Boorstein contributed to this report.

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