David Jackson

USA TODAY

Capping a week of turmoil over his firing of FBI Director James Comey, President Trump told a crowd of college graduates Saturday they should not be afraid to challenge the establishment or government elites who would second-guess whatever they do. 

"Following your convictions means you must be willing to face criticism from those who lack the same courage," Trump said at a commencement speech at Liberty University in Lynchburg, Va.

In an implied blast at his critics, Trump told the Liberty graduates that "Washington is run by a small group with failed values who think they know everything — we don’t need a lecture from Washington on how to lead our lives." 

Trump did not specifically mention Comey or other political disputes that have marked his first four months in office, but made repeated general references to his maverick campaign and presidency. 

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At one point, Trump said, "in my short time in Washington, I've seen first-hand how the system is broken."  At another, he told students and parents at the conservative religious school that "nothing is easier or more pathetic than being a critic." 

Trump also praised the military for its battle against the Islamic State and referred at one point to his recent executive order on religious freedom. 

Speaking at school that bills itself as the world's largest Christian university, Trump made repeated references to God and the role of faith in society. " We don’t worship Washington," he said. " We worship God.” 

The president also engaged in more traditional commencement rhetoric, congratulating the graduates on their accomplishments and lauding the school's academic credentials and football program.  Trump praised the Liberty evangelical community for its political activism, and cited the large support of religious conservatives for his campaign. 

"What will you give back to this country and indeed to the world?"  Trump asked the graduates. 

Earlier, during the Air Force One ride to southwestern Virginia, Trump told reporters that "we can make a fast decision" on a new FBI director, possibly before his departure Friday on a trip to the Middle East and Europe.  Trump said he and his staff are looking at "very well known, highly respected, really talented people, and that's what we want for the FBI." 

Among the names under consideration to be interviewed Saturday, according to a source familiar with the process who spoke on condition of anonymity to discuss internal deliberations: Acting FBI Director Andrew McCabe, Sen. John Cornyn, R-Texas, former Justice Department Criminal Division Chief Alice Fisher and New York state judge and former U.S. Attorney Michael Garcia. 

The search takes place amid an ongoing firestorm over Trump's dismissal of Comey and new questions over whether he taped conversations with the now-former FBI director. 

In a Friday tweet, Trump said Comey "better hope that there are no 'tapes' of our conversations before he starts leaking to the press!" 

Since that comment, neither Trump nor his aides would confirm or deny questions about whether he in fact tapes conversations. 

"I won't talk about that," Trump told Fox News in an interview. " All I want is for Comey to be honest and I hope he will be and I'm sure he will be, I hope." 

Trump, angry over media coverage on the Comey issue, has also threatened to end White House news briefings. 

Democrats, and some FBI officials, charge Trump got rid of Comey in order to impede an investigation into possible collusion between Trump campaign officials and Russia, which tried to influence the 2016 election by hacking prominent Democrats. 

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In a commencement address of her own, U.S. Sen. Elizabeth Warren, D-Mass, told University of Massachusetts-Amherst graduates they should fight for “the principle that no one, no one in this country is above the law and we need a Justice Department, not an obstruction of justice department.” 

Trump has denounced the Russian investigation as a "hoax" and "witch hunt." 

During the commencement address at Liberty's football stadium, Trump lauded students and parents for being "Champions for Christ."  Saying that "there may very well be a president or two in our midst," Trump encouraged young people to get involved in public life and persevere in the face of criticism. 

"A small group of failed voices, who think they know everything, and understand everyone, want to tell everybody else how to live and what to do and how to think," Trump said. " But you aren't going to let other people tell you what you believe, especially when you know that you are right."