The day before Pope Francis will arrive in Mexico for the start of a five-day visit that includes a stop along the US-Mexico border, Donald Trump says that Francis just doesn’t get it.

Asked about the first Latin American pope’s visit to the border, Trump said, “I think that the pope is a very political person.”

“I think he doesn’t understand the problems that our country has,” he said on Fox Business Network’s “Varney & Co.”

“I don’t think he understands the danger of the open border that we have with Mexico. I think Mexico got him to do it because they want to keep the border just the way it is,” he said. “They’re making a fortune and we’re losing.”

The United States does not share an open border with Mexico; that is, a border with limited or no restriction on movement between countries, as exists in the European Union, for example.

In fact, when Francis celebrates an outdoor Mass in Juarez Feb. 17, the fence separating the two nations will serve as a backdrop behind the temporary altar.

Before Wednesday’s Mass, Francis will lead a prayer service with undocumented migrants gathered about 65 feet away, across the Rio Grande in El Paso.

Recent data shows that more Mexicans are leaving the United States than are entering it. And immigration activists say the border is more secure than ever before, noting that the Obama administration has deported more undocumented migrants than any other president.

But that hasn’t stopped Trump from making opposition to illegal immigration a central pillar of his campaign, leading to a resounding win in the New Hampshire primary Tuesday. He has campaigned on the promise to build a wall across the entire length of the nearly 2,000-mile border.

His criticism of the pope is only the latest episode in his campaign that could create friction between the GOP frontrunner and Catholic voters.

Last month, a 2011 Tweet from Trump’s spokeswoman, Katrina Pierson, resurfaced, which some have said is anti-Catholic.

Like most Christian denominations, Catholics do, in fact, trace the founding of their Church to Jesus.

Although Pierson said her account her been hacked, the tweet remains online.

And some US bishops have criticized Trump for his views on illegal immigration and his portrayal of Mexican migrants as “rapists” and drug dealers.

New York Cardinal Timothy Dolan, who leads an archdiocese with a huge Hispanic population, placed Trump in the dark history of American chauvinism, writing in the New York Daily News last August, “Nativism is alive, well – and apparently popular!”

Bishop Kevin Farrell of Dallas also condemned what he called the “déjà vu of immigrant bashing” in a blog post over the summer, reminding American Catholics that they were once subject to the kind of harsh words used by Trump.

Francis concludes his visit to Mexico next Wednesday with the border prayer service.

The visit has been dubbed “Two Nations, One Faith” by event organizers in order to hammer home the Church’s view that the border shouldn’t be a barrier to solidarity between Americans and Mexicans. To further the point, organizers selected a student who lives in Juarez but attends St. Pius X Catholic School in El Paso to greet the pontiff when he arrives in Juarez.