The Vatican department for migrants and refugees has published the collected teachings of Pope Francis on the issue of immigration, reiterating the pontiff’s appeal for a greater openness to migrants.

The massive 488-page tome, titled Lights on the Ways of Hope: Pope Francis Teaching on Migrants, Refugees and Human Trafficking, gathers together the pope’s addresses on immigration, underscoring how central this topic has been to his six-year pontificate.

Immigration and the care of migrants has not only been vital to the pope’s agenda, he has also insisted that it should be of key importance to every Christian and not considered a second-tier issue.

“We often hear it said that, with respect to relativism and the flaws of our present world, the situation of migrants, for example, is a lesser issue,” Francis wrote in his 2018 apostolic exhortation bearing the Latin title Gaudete et Exsultate (“Rejoice and Be Glad”).

“Some Catholics consider it a secondary issue compared to the ‘grave’ bioethical questions,” he said, a position that he finds untenable.

“That a politician looking for votes might say such a thing is understandable, but not a Christian, for whom the only proper attitude is to stand in the shoes of those brothers and sisters of ours who risk their lives to offer a future to their children,” he continued.

“Can we not realize that this is exactly what Jesus demands of us, when he tells us that in welcoming the stranger we welcome him?” he asked.

The pontiff has defended his continual insistence on the issue of immigration by saying it is not just his pet cause but a central teaching of the bible.

“This is not a notion invented by some Pope, or a momentary fad. In today’s world too, we are called to follow the path of spiritual wisdom proposed by the prophet Isaiah to show what is pleasing to God,” he said.

Throughout his pontificate, Pope Francis has sought to bring about a sea change in debates surrounding migration, appealing for a “change in mindset” and insisting that migrants are not a threat to society but, rather, a source of enrichment.

Wishing to counter a negative narrative on mass migration, especially in countries that have been on the receiving end of migratory waves, the pontiff has called for a shift in priorities and mentality.

“This demands a change in mindset,” he said. “We must move from considering others as threats to our comfort to valuing them as persons whose life experience and values can contribute greatly to the enrichment of our society.”

“For this to happen, our basic approach must be to encounter the other, to welcome, to know and to acknowledge him or her,” he said.

The Vatican is in the midst of a two-year campaign aimed at changing people’s minds about migrants, which it inaugurated in September 2017.

“Brothers, we mustn’t be afraid to share the journey! We mustn’t be afraid to share the hope!” Francis said in his announcement of the project called “Share the Journey,” being carried forward by the global Catholic charities network Caritas Internationalis.

Our world “faces not a migration crisis, but a crisis of global solidarity,” Caritas says on its website. “Be part of a worldwide campaign to reach out to migrants, change perceptions, open hearts and minds, and strengthen the bonds that unite us all.”

In various addresses gathered in the new Vatican collection, Pope Francis connected mass migration to climate change, said that resistance to mass migration comes from an “innate fear of the foreigner,” claimed that nations are built by migrants, and insisted that the rights of migrants trump national security concerns.

In our own time, the pope writes in the forward to the text, “movements of people, although entailing challenges and sufferings, are enriching our communities, local Churches and societies in every continent.”

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