The pope made the comments in a message on the theme of "Migrations and New Evangelization" for the World Day for Migrants and Refugees 2012; the text was released at the Vatican Oct. 25 during a news conference.

The World Day for Migrants and Refugees is observed Jan. 15. In the United States, National Migration Week will be celebrated Jan. 9-14.

In his message, the pope called on Christians to pay special attention to migrant workers and their families and to accompany them with "prayer, solidarity and Christian charity."

Christians also should promote political, economic and social policies and strategies that uphold "the dignity of every human person, the safeguarding of the family (and) access to dignified housing, to work and to welfare," the pope said.

Those seeking asylum because of persecution, violence and threats to their lives "need our understanding and welcome," he said. They need respect for their dignity and rights and to become aware of their duties and responsibilities in a new land, he added.

At the news conference, Archbishop Antonio Veglio, president of the Pontifical Council for Migrants and Travelers, said immigrants "must be legitimately legalized, freeing them from the scourges of poverty, exploitation and the trafficking of organs and people."

By helping immigrants obtain legal status and by protecting their dignity, communities can foster real human progress so that migration becomes "a blessing for dialogue among peoples, coexistence in justice and peace, and the evangelical proclamation of salvation in Jesus Christ," said the Italian archbishop.

In his message, the pope said increased human mobility means there are new challenges and opportunities for evangelization.

Every Christian has a duty to evangelize, and the ease of communication and meeting new people who may never have encountered Christ "must reawaken in each one of us the enthusiasm and courage that motivated the first Christian communities to be undaunted heralds of the Gospel's newness," he said.

The presence of people from different nations and cultures means there is greater urgency for dialogue and respect for legitimate differences.

However, secularization and the "fragmentation" of societies that divide people according to cultural or ethnic identities are an obstacle to the unifying vision of one human family, he said.

Much of today's world "is marked by endeavours to efface God and the church's teaching from the horizon of life, while doubt, scepticism and indifference are creeping in, seeking to eliminate all the social and symbolic visibility of the Christian faith," he said.

In such secularized communities, the church is faced with new challenges in helping Christians migrants maintain their faith in their new homelands, the pope said.

The church must develop new pastoral approaches, methods and expressions to help Christian migrants "keep their faith firm even when they are deprived of the cultural support that existed in their country of origin," he said.

The increased mobility of peoples from different nations and cultures in today's globalized world also presents new opportunities to evangelize, to dialogue with other believers and show the unifying force of the Christian vision of one human family in today's multiethnic, multicultural communities, said the pope.