ROME – January 1 is the “World Day of Peace” on the Catholic calendar, with Pope Francis choosing this time around to focus on migrants and refugees. He backed that message up on New Year’s Day on Monday, pointing to migrants and refugees as among the “weakest and most disadvantaged” persons for whom God has special concern.

“I would like once again to raise my voice for these brothers and sisters, who seek a horizon of peace for their future,” the pope said, speaking in his first noontime Angelus address of 2018.

“To find this peace, which is the right of all, many of them are willing to risk their lives in a journey which, in most cases, is long and dangerous, facing hardships and suffering,” he said, quoting from the text of his written message for the day, which was released by the Vatican in late November.

“May we not extinguish hope in their hearts!” Francis said on Monday. “May we not stifle their expectations of peace!”

“It is important that everyone, civil institutions, educational and welfare organizations, and ecclesial realities are committed to ensuring refugees, migrants and everyone a future of peace,” he said. “May the Lord grant us to work in this new year with generosity to create a more supportive and welcoming world.”

The pontiff then entrusted migrants and refugees under the protection of Mary as the Mother of God, adding an off-the-cuff reference to “ancient mystical monks” who taught that in “times of turbulence, it’s important” to seek Mary’s aid.

In his written message for today’s World Day of Peace, Francis asked the world “to embrace all those fleeing from war or hunger, or forced by discrimination, persecution, poverty and environmental degradation to leave their homelands.”

The pope urged policies built on the fundamental values of “welcoming, protecting, promoting and integrating” migrants and refugees, and lent his support to two Global Compacts scheduled to be signed by the United Nations in 2018, one on migrants and the other on refugees, in an effort to bring greater stability to the flow of people around the world.

Francis also denounced what he described as a worrying “spread” of anti-immigrant sentiment.

“Many destination countries have seen the spread of rhetoric decrying the risks posed to national security or the high cost of welcoming new arrivals, and thus demeaning the human dignity due to all as sons and daughters of God,” the pope wrote.

“Those who, for what may be called political reasons, foment fear of migrants instead of building peace are sowing violence, racial discrimination and xenophobia, which are matters of great concern for all those concerned with the safety of every human being,” he said.

At the same time, Francis also acknowledged that “prudence” is required in crafting immigration and refugee policies, including setting the proper limits on how many new arrivals a given society can be expected to absorb.

“Leaders have a clear responsibility towards their own communities, whose legitimate rights and harmonious development they must ensure, lest they become like the rash builder who miscalculated and failed to complete the tower he had begun to construct,” the pope wrote.

Monday is also the feast of Mary the Mother of God on the Catholic calendar, and Francis opened his Angelus remarks with reflections on Mary that largely echoed themes of a homily he delivered earlier in the day in St. Peter’s Basilica.

“The Virgin helps us understand how the Christmas event should be welcomed,” Francis said, “not superficially, but in the heart.”

“She shows us the right way to receive the gift of God,” he said, “conserving it in the heart and meditating on it. It’s an invitation addressed to every one of us to pray while contemplating and tasting this gift that is Jesus himself.”

Francis suggested there’s a clear connection between the example of Mary and concern for migrants and refugees.

“As a mother, Mary plays a very special role: She places herself between her Son Jesus and people, in the reality of their deprivations, poverty and suffering,” the pope said.

After praying the Angelus, Francis added a note of thanks for recent peace initiatives by Catholic organizations organized around the World Day of Peace, including one in Italy sponsored by Caritas, the Italian bishops’ conference, Pax Christi and Catholic Action as well as peace rallies staged around the world by the Sant’Egidio movement under the heading of, “Peace in all lands.”

The pontiff also thanked Italian President Sergio Mattarella for his good wishes, expressed in the Italian leader’s traditional speech to the nation on New Year’s Eve, with Francis saying he hopes the Italian people in 2018 will enjoy “a year of serenity and peace, illuminated by the constant benediction of God.”

(The serenity part, anyway, may be a tough order to fill, since Italy is scheduled to hold a general election on March 4 and most signs point to an acrimonious and tightly contested race.)

The pope then offered greetings to groups on hand in St. Peter’s Square on a chilly Roman New Year’s Day, including pilgrims from New York and a musical band from California. According to the Vatican Gendarmes, 40,000 people turned out on Monday.

The Vatican traditionally regards the holiday season as wrapping up on Jan. 6, when Francis is scheduled to celebrate the feast of the Epiphany. The next day is the feast of the Baptism of the Lord, when the pope customarily baptizes the children of Vatican employees born during the past year.

On Jan. 8, the pope will deliver his annual address to the Vatican diplomatic corps, usually considered his most important foreign policy speech of the year.