on September 10, 2015 at 1:23 PM, updated September 10, 2015 at 1:48 PM
TRENTON — Donald Trump has engaged in yet another war of words with a fellow Republican presidential candidate — this time with Ben Carson, his closest competitor in recent polls.
On Wednesday, Carson questioned the authenticity of Trump's religious faith when speaking to reporters at a rally in California.
On Thursday, Trump shot back at the retired neurosurgeon during a television interview, calling him "an okay doctor" who has held "horrendous" views on abortion.
"Who is he to question my faith?" the billionaire businessman and GOP frontrunner said via phone on CNN's "New Day." "I mean, he doesn't even know me."
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Trump's comments came soon after a CNN/ORC poll released Thursday showed him leading his 16 Republican opponents with 32 percent of the vote.
Carson — who, like Trump, is a political outsider who has never held public office — sits in second place with 19 percent, having jumped 16 percentage points from the group's last survey.
New Jersey Gov. Chris Christie is tied for 10th place at 2 percent.
During the rally in Anaheim, Calif., on Wednesday, Cason was asked by a reporter how he differs from Trump.
"I've realized where my success has come from, and I don't in anyway deny my faith in God," he replied, according to reports. "And I think that probably is a big difference between us."
Asked to explain what he meant, Carson quotes his favorite Bible verse, Proverbs 22:4.
"It says: 'By humility and the fear of the Lord, our riches and honor and life,'" he said, according to reports. "And that's a very big part of who I am. Humility, and fear of the Lord. I don't get that impression with him. Maybe I'm wrong."
Carson, a Seventh Day Adventist, has repeatedly touted his faith on the campaign trail. He broke on the national political scene after delivering 2013 the keynote address at the National Prayer Breakfast.
But Trump said of Carson on Thursday: "If you look at his past, which I've done, he wasn't a big man of faith."
"All of a sudden, he's becoming this man of faith and he was heavy into the world of abortion," Trump said during his CNN appearance.
Carson, a former neurosurgeon at Johns Hopkins Hospital in Baltimore, is vehemently against abortion now. But he conducted medical research on aborted fetuses in 1992.
Trump also questioned if Carson — the first surgeon to successfully separate conjoined twins joined at the head — is qualified to be president.
"He was an okay doctor," the businessman said. "He was just fine."
And he compared Carson to fellow GOP contender Jeb Bush, whom Trump frequently mocks for being "low energy."
"He makes Bush look like the Energizer bunny," Trump said. "He's very low key."
"Ben Carson will not be the next president, that I can tell you," he added.
The words marked a shift in tone for Trump, who recently praised Carson.
"I like Ben a lot," Trump said on "Good Morning America" last week. "He's a good guy.
Carson, meanwhile, told the Washington Post on Thursday that his comments about Trump's faith were misunderstood.
"I would like to say to him that the intention was not to talk to him but about what motivates me," Carson told the newspaper. "If he took that as a personal attack on him, I apologize, it was certainly not the intent."
He added that he won't throw a counter-punch after Trump's remarks Thursday.
"The media frequently wants to goad people into wars, into gladiator fights, you know," Carson told the Post. "And I'm certainly not going to get into that."
Trump has mentioned his faith on a few occasions, noting that he is Presbyterian and that the Bible is his favorite book.
When a moderator asked Trump during a forum in Iowa in July whether he'd ever asked God for forgiveness, the businessman said: "I am not sure I have."
"I think if I do something wrong, I think I just try and make it right," Trump added. "I don't bring God into that picture."
The answer drew some criticism from evangelical voters. And last month, Trump raised more eyebrows when he declined to cite his favorite Bible verse during an interview with Bloomberg News, saying "that's very personal."