By Talal Ansari

The decision to open their church to immigrants wasn’t one Pastor Patrick Shebeck and his 700-member congregation in St. Paul, Minn., took lightly.

“We wanted to be smart about it, so we researched for eight or nine months, sought legal advice and studied the history of sanctuary movements” after the 2016 election, said Pastor Shebeck, of St. Paul-Reformation Lutheran Church.

The church eventually took in four people who had applied for asylum in the U.S. and began providing material support for another person who was in the country illegally.

While many white evangelicals remain core supporters of President Trump and his policies, some churches around the U.S. are taking a different path. As the Trump administration increases immigration enforcement, some congregations are joining synagogues and other religious institutions in opening their doors to provide sanctuary to asylum seekers and illegal immigrants.

In Minnesota alone, around 60 congregations provide sanctuary or supporting services to immigrants living in the U.S. illegally. Nationally, that number is estimated to be around 1,000, according to Church World Service, a faith-based aid organization. More than 70 synagogues around the country have committed to helping immigrants and asylum seekers, according to T’ruah, a Jewish human-rights organization.

“We’re calling it sacred resisting,” said Rev. Noel Andersen, the grass-roots coordinator for Church World Service.

With the number of families crossing the U.S.-Mexico border surging to new records, Mr. Trump is trying new policies to restrict migration.

Mr. Trump signed an executive order in early 2017 allowing the government to fine undocumented immigrants who remain in the U.S. and the people who assist them.

Other new policies include barring asylum claims from people who have crossed through at least one other country on their way to the U.S. and expanding “expedited removal,” or deportation, policy.

Rosa Sabido came to the U.S. from Mexico in 1987 and first sought refuge at Mancos United Methodist Church, in Colorado, in June 2017. She wanted to avoid being deported after her stay-of-removal request was denied. For more than 750 days since then, Ms. Sabido said, she hasn’t set one foot over the church’s property line. She hasn’t had a medical checkup at a doctor’s office, shopped in a store or even taken a stroll around the block.

“I have never left this place. Even to think about leaving in an emergency or extreme circumstances, it really gets me nervous and fills me with fear and panic,” Ms. Sabido said.

Immigration and Customs Enforcement deported 256,085 undocumented immigrants in fiscal 2018, a 13% increase from the previous year and comparable to the number of deportations during former President Obama’s last year in office.

In mid-July, as fears of ICE raids spread, there was an uptick in the number of families seeking sanctuary, said Minister JaNaé Bates, communications director for Isaiah, a coalition of faith groups in Minnesota. “It almost always coincides with the executive orders and threats of harm to immigrant families,” she said, referring to enforcement raidsand the administration’s family-separation policy, among other things.

A spokesman for ICE said the agency continues to focus its limited resources on those who pose the greatest threat to public safety. “ICE only conducts targeted enforcement,” he said.

Many cities and counties around the U.S., however, no longer detain low-risk illegal immigrants just because the ICE asks. The sanctuary-city movement is challenging the crackdown on illegal immigration and putting local governments at odds with the administration. President Trump has threatened to withhold federal money from sanctuary cities and floated the idea of relocating detained immigrants to those cities.

Churches have long served as places of refuge, from sheltering escaped slaves as part of the Underground Railroad to providing safe haven for Central Americans fleeing conflict. Often, they have done so with little interference from the government.

In 2011, ICE designated religious institutions as “sensitive locations,” with protections from immigration enforcement. Still, not every church has embraced the sanctuary approach for undocumented immigrants.

“There are, of course, going to be folks who are going to say this is plain wrong, and others who see this as decidedly too political and radical,” said Ruth M. Melkonian-Hoover, a professor of political science at Gordon College, in Wenham, Mass., who co-wrote a book on the divisions within evangelicalism over immigration politics.

White evangelical Protestants, in particular, remain a strong core of Mr. Trump’s base. Almost three-quarters of white evangelicals support a wall expansion along the U.S.-Mexico border, according to a January 2019 survey by Pew Research Center.

Church leaders, even if they agree with providing sanctuary for the undocumented in principle, may believe their own congregation’s time is better spent aiding immigrants in other ways, such as providing legal assistance, Dr. Melkonian-Hoover said.

Now, many seeking refuge in churches face the possibility of fines.

Citing the Immigration and Nationality Act, ICE since last December has been issuing civil fines of up to $500 a day to people who have been ordered to leave the country or who have been granted voluntary departure but failed to leave, an agency spokesperson said.

“To me, it’s a war against the poor,” said Jim Rigby, pastor of St. Andrew’s Presbyterian Church in Austin, Texas. An undocumented Guatemalan immigrant and her son, who have been taking shelter in his church for the past two years, received a notification that they were fined $303,620 by ICE in July.

“The fines that they’ve sent out, the only purpose of that is fear,” Pastor Rigby said.

The ICE spokesman said, “Unlawfully present foreign nationals are subject to arrest and removal regardless of how long they remain within a designated sensitive location.”

For congregations that have decided to offer sanctuary, the choice isn’t necessarily informed by politics, but by faith. “Jesus himself was a refugee, Mary and Joseph were refugees,” said Pastor Shebeck, of St. Paul-Reformation Lutheran Church.

Write to Talal Ansari at Talal.Ansari@wsj.com

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