Somewhere in the crush of a million or more pilgrims converging on Rome this weekend, Jeanne Caldwell, her sister, Joan Benge, and a friend, Debbie Rebstock, will watch the rare canonization of two Catholic popes Sunday, having traveled 5,000 miles from Metairie to see it.

Political consultant and New Orleans resident Mary Matalin will be there, too, blogging and doing television commentary with her friends and fellow conservatives Peggy Noonan and Kathryn Jean Lopez, self-described “Crazy Catholic Chicks.”

And many locals who can’t make it personally, like Deacon Jim Swiler, who assisted Pope John Paul II during the pope’s historic Lakefront Mass in New Orleans in 1987, will remember — again — the experience of being with someone now formally recognized as a saint.

For Swiler, a layman who is now the chancellor of the Diocese of Houma-Thibodaux, the afternoon of Sept. 12, 1987, remains a highlight in a long career of church service.

It was the main event in the pope’s three-day visit to New Orleans. Swiler stood at the altar with John Paul for 1½ hours , assisting him with the ritual.

“It was a wonderful privilege and great thrill to be in that presence,” Swiler said. “You could tell he had that gift you strive for. You could feel that aura of spirituality around him.”

Swiler said he sensed it only one other time, when he met Mother Teresa, the missionary and nurse to the dying in Calcutta.

On Sunday, Pope Francis will formally declare that John Paul II and another 20th-century pope, John XXIII, who died in 1962, are saints of the Catholic Church.

The two popes are among the relatively few canonized saints whose lives are still within living memory. They demonstrated different ways of exercising the office, and they are heroes to two wings of the church who coexist with some tension today.

Some observers see in the twin canonization a shrewd leadership move by Pope Francis in that it honors champions of two different constituencies.

John XXIII is beloved by liberals as the reformer whose Second Vatican Council opened the church to the world.

Two decades later, John Paul II became conservatives’ hero for reining in the “excesses” of many of those reforms and re-establishing firm lines the church would not cross on matters like homosexuality, birth control and women’s ordination.

In Catholic piety, saints are ordinary people — including tens of millions of deceased, nameless friends and relatives — thought to be with God in heaven and thus able to intercede in prayer on behalf of people on earth.

But upper-case saints, like those for whom churches and parishes are named, are the relative few on whom the global church publicly bestows hero status. It declares their sainthood with the kind of solemn ceremony that will be on display Sunday, places their feast days on its calendar and points to them as public models of faith.

Caldwell, whose family owns a home health care agency, was a child at St. Mary Magdalene Catholic School in Metairie when John XXIII’s Second Vatican Council revolutionized common worship. In the United States, the Mass shifted from impenetrable Latin to understandable English.

“That opened a whole world up to me as a child. I thank John XXIII for that,” she said.

Years later, as an adult working with young people at St. Jerome and St. Clement of Rome parishes, she watched John Paul II invite them to faith and saw the responses of many, she said.

“I could see young people embracing faith because of him,” she said. “That was a beautiful thing.”

John Paul’s papacy, which ended in 2005, was long and consequential. His support of the Solidarity movement in Poland helped topple Communism. His travels redefined the papacy. Within the church, he defended orthodoxy with authoritarian papal power.

However, of the two popes, John Paul has many more critics, especially for his perceived passivity in the early 2000s, when the child sex abuse scandal exploded in the Catholic Church.

John Paul, then in the advanced stages of Parkinson’s disease, let events unwind largely without his intervention, which child advocates widely interpreted as rejection of their pleas for support.

Many Catholics also were dismayed by the hospitality he offered to Boston’s Cardinal Bernard Law, who resigned because of the scandal and moved to Rome, and his public affection for the Rev. Marcial Maciel Degollado, the founder of the Legionaries of Christ, who later was exposed as a serial abuser of seminarians and the secret father of two families.

Still, millions placed John Paul’s flaws in the context of his virtues. Calls to canonize him began even as he was being buried.

His successor, Pope Benedict XVI, set aside the usual waiting period and placed John Paul on the fast track to this weekend’s ceremony.

John Paul, born Karol Wojtyla in Poland, will be canonized in what may be record time for modern saint-making, only nine years after his death.

“There was no question where that was going to lead, once it was announced he was on the fast track,” Swiler said.

By contrast, John XXIII, formerly Angelo Roncalli of Lombardy, was a different kind of pope.

He served five years, from 1958 to 1963. Short, rotund and genial, he exuded an image of jovial simplicity at odds with the austere pomp of his predecessors. Soon the world began to call him “Good Pope John.”

But underneath that nonthreatening surface beat the heart of a radical. Elected as a caretaker pope expected to do nothing, John instead changed everything.

It was John who, without consulting his horrified inner circle, convened the Second Vatican Council from 1962 to 1965 to “throw open the windows” of the Catholic Church to reform. The council loosed pent-up forces of change — in modes of worship, new roles for laypeople, new approaches to Scripture — that delighted many Catholics and dismayed others, and which continue to reverberate half a century later.

Advocates for his sainthood successfully made the case for his life of holiness, and they produced evidence of one miracle said to be the result of John’s intercession with God. Normally, evidence of two such miracles is needed for canonization, but Pope Francis waived the need for a second miracle in John’s case and announced the two popes would be elevated to sainthood on the same day.

New Orleans Archbishop Gregory Aymond, then 37, was a relatively new monsignor running Notre Dame Seminary when he served as one of several coordinators of the 1987 papal Mass at the Lakefront.

Today he is an archbishop, living in the residence where John Paul ate and slept for two nights as the guest of then-Archbishop Philip Hannan.

A plaque on Aymond’s dining table marks the occasion. There is another on the headboard of his bed.

Aymond said there are times as he moves about his residence that this thought impresses him: “I’m literally walking in the footsteps of a saint.”