2016 Candidates React to Pope Francis-Donald Trump Back-and-Forth

— -- Donald Trump’s fellow Republicans joined the fray today in response to the pope’s suggestion that the New York real estate mogul was “not Christian.”

“A person who thinks only about building walls, wherever they may be, and not of building bridges, is not Christian,” Pope Francis said during a flight from Mexico to the Vatican Wednesday night.

After the Republican presidential front-runner called the pope’s comments “disgraceful,” others weighed in from the campaign trail:

Jeb Bush

The former Florida governor pushed back a bit.

"I don’t question anybody’s Christianity because I honestly believe that’s a relationship you have with your creator and it only enables bad behavior when someone from the outside of our country talks about Donald Trump,” Bush said while campaigning today in Columbia, South Carolina, before the Saturday primary there.

Back in January, however, Bush had some strong words for the real estate mogul and his faith, calling him a “flip-flopper." "Trump views all this not from a position of his faith, he views it all as politics. I think faith goes way beyond politics,” he said to reporters after a campaign rally then.

Bush said today he supports walls with fencing where it’s appropriate and that a strategy to protect the border 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.”

Bush, who is Catholic, said he respects the pope, but won’t be looking for advice from the pontiff on policy matters.

“I think it’s OK, as a Catholic, to get my guidance as a Catholic from the pope but, certainly, not economic policy or environmental policy,” Bush said. “I respect the pope, his voice will be heard, but dealing with ISIS, we need someone who has a steady hand and a strategy and I’m the only guy who laid out a strategy prior to the attacks and I’m going to stick with that being the important thing."

Marco Rubio

The Florida senator avoided commenting on the recent exchange between rival Trump and Pope Francis in an interview with CNN.

“I think the Holy Father recognizes, or should recognize and I believe he does, how generous America is.” Rubio told CNN’s Jake Tapper Thursday afternoon, adding later, “So when it comes to accepting both refugees and immigrants, no nation on this planet is more welcoming, more open, or more compassionate than the United States.”

Rubio also argued that because America is a sovereign country, it has “a right to have immigration laws and it has a right to enforce immigration laws.”

“As far as building walls on the border, its wall is not just about immigrants. It's also about potential terrorists crossing that border, not to mention the drugs coming across that border and the human trafficking because people know they can get people across the border.”

Ben Carson

The retired neurosurgeon, who is a Seventh-day Adventist, also chimed in today, saying, “it would be hilarious if it weren’t so sad.”

Despite Pope Francis’ characterization of Trump, Carson told Fox Business Network’s Neil Cavuto in a telephone interview he would not “judge” his fellow GOP contender’s faith.

“I am not going to judge Donald Trump in terms of whether he is a Christian or not. Some of the things he does may not be suggestive of Christianity, but then again all of us have weaknesses and shortcomings. That is what it is all about,” Carson said.

Ted Cruz

Before his stop in Easley, South Carolina, the Texas senator responded briefly to the pope's comments about Trump.

“Listen, that's between Donald and the pope,” Cruz, a Southern Baptist, said today. “I'm not going to get in the middle of that. I'll let them work it out.”

John Kasich

The Ohio governor marched to the beat of his own drum, as he responded to the pope’s comments on Trump in utter disbelief.

“First of all, I love the pope,” he said while campaigning in Clemson, South Carolina, today.

“He’s not a guy who’s been running around wondering who’s pure and who’s not. So if he said that, I’m sure he would regret having said that, because it’s not up to any of us to judge who’s good and who’s bad.”

But Kasich, a former Roman Catholic who now belongs to the Anglican Church in North America, did say he believes in building a wall.

“I not only believe in building a wall, you know, to make sure we can have orderly entrance into our country, but I believe in building bridges, too,” Kasich said.

ABC News’ Jessica Hopper and Tom Llamas contributed to this report.