Televangelist Jerry Falwell Jr. has given his endorsement to Donald Trump, calling the Republican presidential front-runner a "God-fearing president-in-waiting."

However, Mark DeMoss, the chief of staff of Falwell's father, does not agree.

DeMoss told The Washington Post that Trump's "insult-laden campaign has been a flagrant rejection of the values Falwell Sr. espoused and Liberty promotes on its campus."

"Donald Trump is the only candidate who has dealt almost exclusively in the politics of personal insult," he said. "The bullying tactics of personal insult have no defence—and certainly not for anyone who claims to be a follower of Christ. That's what's disturbing to so many people. It's not Christ-like behavior that Liberty has spent 40 years promoting with its students."

DeMoss said he tried to share his views about Trump with Falwell Jr., but in the end, it "appears to be something we're just going to disagree on."

"I've held my tongue," DeMoss further said. "I think a lot of what we've seen from Donald Trump will prove to be difficult to explain by evangelicals who have backed him. Watching last weekend's escapades about the KKK, I don't see how an evangelical backer can feel good about that."

DeMoss was referring to Trump's initial failure to disassociate himself with notorious former Ku Klux Klan leader David Duke after the latter told listeners of his radio programme to "get active" for Trump. When criticism started pouring in, Trump was eventually forced to categorically disavow Duke's endorsement.

Meanwhile, when Falwell Jr. compared Trump to his late father, DeMoss took offence, saying that "Trump certainly does not demonstrate Jerry Falwell Sr.'s graciousness and love for people."

"Jerry Falwell Sr. would never have made fun of a political opponent's face or makeup or ears. He would not have personally insulted anybody—ever," DeMoss said.

As for Falwell Jr., he finds DeMoss' animosity towards Trump "puzzling," adding that he "was disappointed" with him. Falwell also insists that his endorsement of Trump is not one he has imposed on Liberty's students or faculty.