A federal jury last week acquitted Espy of all 30 charges brought by Independent Counsel Donald Smaltz. Espy was alleged to have accepted illegal gifts from companies he regulated.
"I think all of us have been deeply moved to see this good man grow in mind, body and spirit through this difficult ordeal," Clinton said.
Espy said God had used the experience to humble him. "I was on an adrenaline high. And that high evolved even into something like a sense of invincibility," he said. "But then I got knocked to my knees."
Espy had been a political star until Smaltz's investigation. Before being chosen by Clinton in 1993 to become the nation's first black agriculture secretary, he was Mississippi's first black congressman since Reconstruction, representing poor residents of the Mississippi Delta.
When the prosecutor's investigation revealed that Espy had received thousands of dollars' worth of gifts from companies he regulated, then-White House Chief of Staff Leon Panetta asked for Espy's resignation.
The jury last week said Smaltz had failed to show that Espy had done anything wrong.
But the acquittal came after a four-year, $17 million investigation that left Espy jobless and owing $1.5 million in legal fees. The investigation even touched family members: His brother, Henry Espy Jr., was charged and later acquitted of charges stemming from his failed bid to win his brother's congressional seat. Henry Espy later lost his bid for re-election as mayor of Clarksdale, Miss.
"I know I am mentally stronger," the former Cabinet member told the audience that included Labor Secretary Alexis Herman, Environmental Protection Agency Administrator Carol Browner, former Energy Secretary Hazel O'Leary and the Rev. Jesse Jackson. "I know that I am spiritually stronger," he said.
Espy's portrait was completed in 1995, but he asked that it not be hung right away. "I did not want it shown until the clouds over me had cleared," he said.
For now, Espy said, he plans to get married in March and find a job. He said he and Clinton have discussed his future but gave no details about the conversations.
Espy's portrait, by Mississippi artist Jason Bouldin, will hang with those of other past secretaries in the department's patio, which he calls "a place of honor."
Comparing himself to the biblical David, Espy said he learned a lot in the last four years. "I want to thank the Lord publicly for allowing me to get up off the floor," he said.
And indeed, in his portrait, he is standing.