The Trump-Cruz feud gets nasty

Speaking before a crowd of more than 11,000 students and locals at Liberty University in Lynchburg, Virginia, Donald Trump made no mention of Texas Senator Ted Cruz.

It was practically the first time he'd stopped talking about his presidential rival in the week since their once chummy relationship soured amid a flurry of exchanged insults and questioned political credentials.

Despite a storm of tweets over the weekend blasting Mr Cruz and a round of insult-laden television interviews on Sunday, it's perhaps not surprising that Mr Trump held his tongue at the university founded by the late evangelical leader Jerry Falwell in 1971.

Both Mr Cruz and Mr Trump are battling for the sizeable religious conservative vote in Iowa - which holds its first-in-the-nation presidential caucuses in two weeks - and it's a crowd that Mr Cruz usually seems more comfortable with.

Last March, Texas Senator Ted Cruz launched his bid for the Republican presidential nomination at Liberty University, speaking intimately about his faith and his father, a firebrand evangelical pastor.

Mr Trump, on the other hand, doesn't quite have the same religious bona fides, despite his best attempts. Last September, he proudly held up his childhood Bible at the Values Voter Summit in Washington, DC. And at one point during his hour-long speech at Liberty, he tried to cite a biblical passage about faith and liberty.

The Bible has been brandished several times

Unfortunately for Mr Trump, he referenced "Two Corinthians" instead of "Second Corinthians".

The crowd laughed.

"I always think it's entertaining when people try to throw the Bible into their speeches," Josh Schumacher, a student in his third year at Liberty, said after the speech. "I think it's sometimes just a ploy to get us to buy into what they're saying."

Mr Trump did benefit from a glowing introduction from Liberty University President Jerry Falwell Jr, however, who praised the businessman as one of the "greatest visionaries of our time" and likened him to his famous father.

"Trump can't be bought," he said. "He's not a puppet on a string like so many other candidates."

Liberty University is a Christian institution

That could be read as a tacit boost of Mr Trump over Mr Cruz, as Mr Trump has recently attacked the Texas senator for being in the thrall of his big-ticket campaign donors.

Once upon a time, Mr Cruz and Mr Trump had nothing but kind words for each other. Mr Cruz invited Mr Trump to join him in speaking at a rally in front of the US Capitol, protesting the US-Iran nuclear arms agreement.

And while other candidates criticised the businessman for his call to temporarily close the US border to all Muslims, Mr Cruz was more restrained.

Mr Cruz said he wouldn't engage in a "cage match" with Mr Trump, tweeting that the New Yorker was "terrific".

But as the Iowa caucuses approach, and Mr Cruz and Mr Trump are locked in a battle for first place according to polls, the sparks have flown.

His ceasefire with Cruz broke publicly at the Republican debate last week

For the past week, Mr Trump has questioned Mr Cruz's eligibility for the presidency, given that he was born of an American mother on Canadian soil.

Mr Cruz has returned fire, saying Mr Trump embraces the liberal values of his New York City home town. Their acrimony was one of the headlines of the Republican presidential debate last Thursday.

Since then Trump has attacked the senator as a hypocrite and a "nasty man".

"Nobody likes him anywhere once they get to know him," Mr Trump said on Sunday. "He's got an edge that's not good. You can't make deals with people like that."

Mr Cruz responded on Monday by comparing Mr Trump unfavourably to conservative patron saint Ronald Reagan and saying he is unqualified for the presidency.

Dylan Engel said the feud is upsetting

David Barton, who chairs a group supporting Mr Cruz, went one step further.

"Donald Trump's about-face, negative attacks on Ted Cruz are proof he has neither the temperament nor judgement to lead our country," he said in a statement. "It proves Trump is the ultimate opportunist."

Dylan Engel, Liberty student, said that he supports both Mr Cruz and Mr Trump, and finds the growing rivalry between the two upsetting.

"I like how outspoken Trump is," he said. "I believe today we need to fight political correctness. We're being torn apart from the inside."

He added, however, that he's impressed that Mr Cruz hasn't backed down from Mr Trump's attacks.

"Ted Cruz stood his ground," he said.

It seems the Trump-Cruz battle is just warming up.