Following a visit to Mexico, Pope Francis criticized
the Republican front-runner on his desire to build a wall between the United States and Mexico to prevent illegal immigration.
"A person who thinks only about building walls, wherever they may be, and not building bridges, is not Christian. This is not in the gospel," the Pope told journalists who asked his opinion on Trump's proposals to halt illegal immigration.
Florida Sen. Marco Rubio said he did not hear the comments, but said keeping Americans safe is the federal government's number one obligation is safety.
When asked by CNN on "The Lead with Jake Tapper" about the Pope's remarks, Rubio defended the United States
as the "most compassionate and open country in the world on legal immigration," and defended the government's right to implement and enforce immigration laws as it sees fit.
"I think the Holy Father recognizes or should recognize -- and I believe he does -- how generous America is," Rubio said. "We accept, every year, close to a million or over a million people every year as permanent residents of the United States. No other country even comes close."
Former Florida Governor Jeb Bush, who is also Catholic, would not dismiss Trump's Christianity based on his desire to build a wall, but criticized his immigration policy.
"I think his Christianity is between him and his creator. I don't think we need to discuss that," he said. "As related to his policy relating to ISIS, he's not the right guy to be Commander-in-Chief."
"I respect the Pope. His voice will be heard. But dealing with ISIS, we need someone who has a steady hand and a strategy," he added.
Bush said supporting a wall "where it's appropriate" is not necessarily "an un-Christian thing."
"Across the board we ought to have a strategy to protect our border. That is clear," he said. "But that is not an un-Christian thing to do to make sure that people don't come across our border illegally. That's a just thing to do."
Texas Sen. Ted Cruz refused to weigh in, saying on the campaign trail Thursday, "Listen, that's between Donald and the Pope, I'm not going to get in the middle of that, I'll leave it to the two of them to work it out."
Trump later hit Cruz over his truthfulness at a campaign rally in Gaffney, South Carolina, on Thursday afternoon, saying "he holds up his Bible and then he lies," a line he's used several times this week.
Ben Carson said he "would not personally judge" another person's Christianity.
"While everyone is entitled to their own opinions, I would not personally judge whether or not someone is a Christian. I am a strong Christian myself, and as such do not pass judgments on others' personal beliefs," he told CNN in statement.
Trump immediately fired back on Thursday, calling Francis' comments "disgraceful."
"No leader, especially a religious leader, should have the right to question another man's religion or faith," he said in statement. Trump added that the government in Mexico, where Pope spent the past five days, has "made many disparaging remarks about me to the Pope."
"If and when the Vatican is attacked by ISIS, which as everyone knows is ISIS's ultimate trophy, I can promise you that the Pope would have only wished and prayed that Donald Trump would have been president," Trump added.
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Reactions came in to the Pope's comments came in beyond the campaign trail.
White House Press Secretary Josh Earnest said President Barack Obama's Christian faith shaped the values and priorities that he champions.
"We've noted on a number of occasions that a number of those values and priorities are not shared by Mr. Trump," Earnest said.
"I will however extend to Mr. Trump the courtesy he has not extended to the president and not use this opportunity to call into question the kind of private personal conversations he is having with his God," he added.
New York City Mayor Bill De Blasio took to Twitter to contrast the Pope and Trump.
".@Pontifex calls for compassion for immigrants and respect for all humanity while @realDonaldTrump denigrates women, Mexicans, Muslims," he tweeted.