CNS FILE PHOTO | KEITH DANNEMILLER
People pack a room at the St. Juan Diego Migrant House, a shelter and sanctuary for travelers, in a suburb of Mexico City.
Christians need to offer migrants special care, ranging from prayer and concrete aid to promoting policies that uphold immigrants' rights and dignity, Pope Benedict said.
Modern migration represents "an unprecedented mingling of individuals and peoples, with new problems not only from the human standpoint but also from ethical, religious and spiritual ones," he said.
The influx of people from all corners of the world offers new opportunities to evangelize and to provide material and spiritual care to those in need, he said.
The World Day for Migrants and Refugees is observed Jan. 15.
The pope said Christians 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."