PHILADELPHIA — The palpable energy 20,000 visitors brought to downtown Philadelphia for the World Meeting of Families intensified Friday when police closed streets to prepare for up to 1 million people who hope to see Pope Francis.

Dozens of confused pedestrians trying to find detours around the barricades early Friday afternoon stopped on a corner of Arch Street in front of the Pennsylvania Convention Center to ask directions from Peter and Toby Christensen, an LDS couple from Colorado working as volunteers this week for the Catholic Archdiocese of Philadelphia.

"We're known as the Mormon volunteers," said Peter Christensen, who served as president of the Nevada Las Vegas Mission of The Church of Jesus Christ of Latter-day Saints from 2008-11.

"What a great way to do interfaith work with our Catholic friends and support the family," Toby Christensen said. "It's been so great to see their devotion to the family and to stand up with them."

One of the most striking lessons they learned was that Africans they spoke with are deeply concerned that Western influences are beginning to destabilize families in their nations. That also was a theme batted around at a press conference here this week by Elder D. Todd Christofferson of the LDS Church's Quorum of the Twelve Apostles, Cardinal Gerhard Muller of the Vatican and Pastor Rick Warren of the Saddleback Church.

More on that later.

The roots of how a pair of 50-something Latter-day Saints traveled 1,750 miles from the Denver suburb of Lakewood to work as volunteers for a Catholic diocese are found in the story of President Henry B. Eyring, First Counselor in the LDS First Presidency, speaking at a Vatican conference on marriage last year.

When the Christensens watched his speech online, they also caught the invitation to the eighth World Meeting of Families issued then by the Archbishop of Philadelphia, Charles J. Chaput, the former archbishop of Denver from 1997-2011.

The Christensens remembered that he was good to Latter-day Saints in Denver, and they called the archdiocese of Philadelphia. They filled out an online form and then traveled to Philadelphia last month from Washington, D.C., where they spent the summer, to interview for their positions.

"They wanted to know our willingness to be outgoing, friendly — a lot of the things that go hand-in-hand with being an LDS missionary," Peter Christensen said.

He became one of 200 volunteer captains for a sea of 10,000 volunteers providing hospitality and looking out for the safety and special needs of visitors.

"It's just front-line volunteering," Peter Christensen said. "We've loved it."

Saturday, the Christensens will help during the first day of the pope's visit. During the week, they volunteered three hours a day, then sat in for free on sessions of the World Meeting of Families.

"My favorite was a discussion on the integrity of marriage, that marriage can't be changed just by changing the definition. For Catholics, it's a sacrament — for us it's an ordinance — with spiritual meaning in creation."

The Christensens met three Nigerian women who cheered when they learned the Mormon couple has been married 35 years. They cheered louder when they found out the Christensens had five children.

One of the women has eight children, the other two have four apiece.

"They were excited to see people who believe in the family the way they do," Toby Christensen said.

They also were angry and worried.

"They see the culture on the Internet destroying the family in Nigeria," Peter Christensen said.

That became a surprising subject of a press conference Thursday for the launch of a book made up of talks from the Humanum interfaith conference on marriage at the Vatican last year.

Two representatives of American black churches called for a Humanum conference in Africa to help the growing Christian churches there against Western influences that destabilized families in Europe and America.

"Africans need to know we are in their corner," said Jacqueline Rivers, executive director of the Seymour Institute for Black Church and Policy Studies.

The suggestion that Africa should become the battlefield on the family because it quickly is gaining gravity as what one participant called "the future of the Christian church" prompted a strong statement by Cardinal Gerhard Müller, the Vatican's overseer of Catholic doctrine.

The battlefield for this agenda is the United States," said Cardinal Müller, a German. "America is influencing Europe, and from Europe it's going to Asia and to other countries. ...

"We must continue this worldwide collaboration of religions, but we must also think in strategical terms, where is the beginning of this social sickness? I think it is the United States," he added, specifically singling out television shows.

Peter Christensen, who retired as the CEO of Prime Performance, a consulting company he founded to evaluated how well banks interact with customers, and who ran a U.S. Senate campaign in Alaska, is intrigued by the dilemma.

"It will be interesting to see where this goes from here, because the dedication to family among Africans and South Americans is so intense," he said. "We could learn so much from them."

Meanwhile, the Christensens will finish out their stint as regular Mormons joining a Catholic event, the way Elder Christofferson did Thursday by making a presentation at the World Meeting of Families.

"We're often asked what parish we're from," Peter Christensen said. "We tell them we're from the Lakewood Colorado Ward of The Church of Jesus Christ of Latter-day Saints.

"They look at us with surprise, but this has been such a mutual effort for what the church feels is so important, and that's to strengthen families. It's worth it."

Email: twalch@deseretnews.com