"We are not only citizens of this blessed country; we are children of the same awesome God," he said Monday at an interfaith breakfast with about 150 Chicago religious leaders.
"Religion is a source of unity and strength in America," he said.
On Sunday, touching on the constitutional separation of church and state, Lieberman told members of a black church in Detroit that he hopes his candidacy as an Orthodox Jew will reinstate "a place for faith in America's public life."
"As a people, we need to reaffirm our faith and renew the dedication of our nation and ourselves to God and God's purposes," Lieberman, the first Jew to run for national office on a major party ticket, told about 500 members of the Fellowship Chapel.
The Connecticut senator, who supports a moment of silence in public schools, though not necessarily a moment of prayer, also gave a nod to nonbelievers. He said people of faith must "reassure them that we share with them the core values of America, that our faith is not inconsistent with their freedom and our mission is not one of intolerance, but one of love."
Lieberman's aides had said he would discuss health care on Sunday, but the issue barely came up. He focused almost exclusively on morality and religion.
While quietly calling Lieberman's religion a media-made distraction, his aides nevertheless appear to be delighted with the reception he has been getting from audiences of different faiths.
Speaking from the pulpit Sunday, Lieberman sprinkled his speech with biblical references from the Old Testament and received four standing ovations.
He said the nation has lost its moral foundation in part because the constitutional guarantee of freedom of religion has been confused to mean "freedom from religion." He said he hopes his candidacy will change that.
"I hope it will enable people, all people who are moved, to talk about their faith and about their religion, and I hope that it will reinforce a belief that I feel as strongly as anything else that there must be a place for faith in America's public life," he said.
Lieberman said Americans should break down the "flimsy lines" separating those of different faiths "to sing together His holy name."
In the past, Lieberman has often spoken of his religion and in his recent book, In Praise of Public Life, he wrote that he sees religious faith as a way to rebuild "what has come to feel like a crumbling moral framework in the life of our nation." But until Sunday, he had not made that message a part of his campaign.
He didn't mention the effects of President Clinton's affair with Monica Lewinsky on the nation. Instead, he celebrated the strong economy, more jobs and low crime rate as accomplishments of Mr. Cinton and Vice President Gore over the last eight years. He likened them to Moses.
"In some sense, you might say the Red Sea finally parted and more Americans than ever before walked through behind President Bill Clinton and Vice President Al Gore," Lieberman said.
Before Lieberman took to the pulpit, the Rev. Wendell Anthony, pastor of the Detroit church and president of the NAACP's largest chapter, recalled for worshippers how Lieberman in the 1960s had marched on Washington with Martin Luther King, Jr. and went into Mississippi to register black voters.
He criticized Republican nominees George W. Bush and Dick Cheney in the process.
"It does mean something," said Anthony, shouting in a lyrical cadence, "for I ain't read nothing about no Bushes in Mississippi ... I ain't seen no Cheneys on no freedom buses."
Later, Lieberman recalled how he had spoken at a civil rights rally in Bridgeport, Conn., in the 1960's just before King and that the civil rights leader had remarked, "Very good, young man."
"I had actually thought I heard the voice of Moses," Lieberman said.