He said America has developed a "heart problem" because religion and politics are being used to "camouflage meanness."
Watch Barber's entire speech
"We must shock this nation with the power of love," he said. "We can't give up on the heart of our democracy, not now, not ever."
Barber is the campaign leader of the Moral Monday movement here in North Carolina. His speech has drawn national attention, with the Washington Post calling it the most engaging of the convention.
Representative Chris Sgro of Greensboro was in the audience. He told ABC11 Friday that Barber's message at the DNC will likely elevate him to speak about social and civil justice issues on more national stages.
"Reverend Barber's comments weaved together seamlessly the notion that black, white, Hispanics, gay, straight, transgender, we all must come together if we are ever going to progress in this country," he said.
But critics of the speech say Barber is too one-sided on the issues when he represents a civil non-partisan civil rights organization
"There ought to be someone who stands up for African Americans, somebody who wants the unemployment lowered - which Governor Pat McCrory has delivered - somebody who doesn't think we should have uncontrolled, low cost labor go across the border, somebody like Donald Trump," offered Dallas Woodhouse with the NC Republican Party.
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