ROME – When she first heard that Pope Francis wanted her to write the meditations for the world’s most followed Way of the Cross ceremony, Italian Sister Eugenia Bonetti said she was “embarrassed” but soon realized that it could be a “great opportunity.”

An opportunity “not for me, but for the many people who through the years we’ve met, we’ve helped, we’re helping,” the 80-year-old nun told Vatican News. “People with whom we’ve shared a Calvary.”

Bonetti, a member of the Consolata sisters, has spent most of her long career working with victims of modern-day slavery, and today serves as the president of the association “Slaves no More.”

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She’s been tapped to write the reflections for the Way of the Cross that Francis will lead in Rome’s Colosseum on Good Friday, usually attended by tens of thousands and followed on TV by millions.

Each year, the pope asks a different person to write the commentary and prayers, and Bonetti is not expected to go “soft” as she’s not one to mince words.

Speaking with Crux in 2017 about helping women forced into prostitution on the streets of Italy, she said: “To be there and to suffer with and for them, even if nothing changes, gives witness.”

“We are responsible. We are criminals. We should really be sentenced for life! For these are the crimes against humanity, which cry for vengeance before God. We must do all that is possible to give women back their dignity,” she said, pointing her finger at all those who exploit women for profit and all those complicit in the system.

Bonetti is a leader among religious women working against human trafficking. She started and led anti-trafficking initiatives for the Italian Union of Major Superiors and helped educate officials in Italy and the United States about the problem.

Human trafficking is often described as a hidden crime, making it hard to quantify. However, it’s considered to be the third most profitable illegal industry, behind arms dealing and drug trafficking. It affects between 20 to 40 million people around the world forced to work in slave-like conditions in prostitution and child labor, or who become victims of organ trafficking. It’s estimated to generate $150 billion in annual profits.

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Numbers aside, Francis has seen the fight against this illegal industry, a “crime against humanity,” as a core social concern of his pontificate. Prior to that, it was a priority for then-Cardinal Jorge Mario Bergoglio, who fought modern-day slavery in Buenos Aires.

On his way back from Morocco March 31, Francis told journalists he’d once worked with the city’s mayor to produce a non-binding resolution forcing hotels to have signs in the lobby saying prostitution with minors was banned, but “not a single one would put it up.”

An upcoming conference on “Pastoral orientations on Human Trafficking,” organized by the Migrants and Refugee section of the Vatican’s Dicastery for Integral Human Development, which answers directly to the pope, gives a wide meaning to modern-day slavery and shows just how widespread the problem is.

Topics at the April 8-11 conference include the situation of construction workers, domestic workers, the maritime industry, modern technology industries, agriculture, supply chains, the business connection, special vulnerability of women, children and adolescents. But the conference will also look into forced marriage, servitude, forced begging and organ-harvesting, and the connection between slavery and the ongoing migrant crisis.

On Thursday, Francis is scheduled to speak to participants, who include cardinals, religious sisters (among them Bonetti), medical doctors, and officials from various governments and the United Nations.

Among other signs of Francis’s commitment, in 2014 he summoned Anglican, Orthodox, Hindu, Buddhist, Jewish, and Muslim leaders to sign a joint declaration against modern slavery in the sense of human trafficking, forced labor, prostitution, and organ trafficking, declaring it a crime against humanity.

During a youth symposium against modern slavery organized at the Vatican that same year, the pope called for a hands-on approach.

“Collaborating with this cause is not enough for a Christian,” the pope said. “We’re called to commit,” he said, even if it means risking one’s life.

The theme of Francis’s Message for the 48th World Day of Peace, held Jan. 1, 2015, was “Slaves no more, but brothers and sisters.”

“We ought to recognize,” Francis wrote, “we are facing a global phenomenon which exceeds the competence of any community or country. In order to eliminate it, we need a mobilization comparable in size to the phenomenon itself.”

In 2015, Francis instituted the World Day of Prayer and Reflection against Human Trafficking, marked Feb. 8. The date is the feast of St. Josephine Bakhita, considered a patron for trafficking victims. Born in 1868 in Darfur, Sudan, she was kidnapped at the age of nine and sold into slavery, first in her country and later in Italy. She died in 1947 and was declared a saint by Pope St. John Paul II in 2000.

It’s also on John Paul’s watch that the Santa Marta Group was born, a coalition between nuns and the police launched in the United Kingdom with the support of Cardinal Vincent Nichols, which has since become a global brand.

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As archbishop of Buenos Aires, Bergoglio sponsored an NGO called “La Alameda” that fed him information about slave labor in Argentina’s clandestine sewing shops and also human trafficking for prostitution. The future pope would find work and asylum for survivors.

During a Mass in a Buenos Aires train station in 2012, he compared the city to a “butcher shop” that takes away the dignity of people trapped by these networks. He also denounced local police and the legal system for accepting bribes from traffickers, saying that “without them, these mafias wouldn’t exist.”