Pope Francis said that "no people is criminal and no religion is terrorist" in a welcome letter read aloud at a conference on economic inequality that opened Thursday in the small farming city in California.
The gathering of Catholic clergy and activists in Modesto, California, came as the world grapples with the impact of President Donald Trump's efforts to change U.S. immigration policy.
"Do not classify others in order to see who is a neighbor and who is not," the pope said in a letter that was also distributed. "You can become neighbor to whomever you meet in need, and you will do so if you have compassion in your heart."
The pope said that he was not speaking of anyone in particular in pointing out people who scapegoat, but of a social and political process that flourishes around the world.
Trump's name does not appear on the agenda, but his recent announcement of a crackdown on people illegally in the country and limitations on who is allowed into the U.S. are likely to be discussed by social justice activists and faith leaders.
A handful of delegates canceled their attendance, fearful of the U.S. political climate surrounding immigration, said Joseph Fleming of PICO National Network, a faith-based community organizing network also sponsoring the event. He declined to identify them.
"What we're finding is that some of our immigrant delegates are, ironically for a meeting to discuss exclusion and the exclusion of immigrants, are feeling like it's not safe to travel," he said.
More than 600 people including representatives from Argentina, Brazil and Mexico are expected.
Modesto lies in California's agricultural heartland where Latino immigrants represent a significant part of the labor force for the area's farmers. It's the first time that the event will be held in the United States after Pope Francis nearly three years ago launched global meetings to explore the "economy of exclusion."
"We're a nonpartisan group, but the truth of the matter is the gathering is made up of people feeling a lot of fear and a lot of pain," said Trena Turner, pastor of the non-denominational Victory in Praise Church in Stockton.
The conference was scheduled before the U.S. presidential election and before the Trump administration issued its ban on travelers from seven predominantly Muslim countries.
After losing a legal fight in federal court to maintain the ban, the Trump administration said in court documents on Thursday that it wants a pause so it can issue a replacement ban as it strives to protect the nation from terrorism.
Among those speaking Friday is Zahra Billoo, executive director of the San Francisco Bay Area chapter of the Council on American-Islamic Relations.