Washington (CNN) Roger Stone 's criminal trial exposed on Thursday a pile of lies in texts and emails Stone sent to or received from others -- with testimony peppered by Stone's foul-mouthed written insults and one witness' sense of humor.

In all, the day in court largely focused on how prosecutors believe Stone lied to Congress and how he then pressured his associate, comedian and radio host Randy Credico, to do the same. It also offered a window into how the self-described political "dirty trickster" mistreated others in private, all while pushing for Donald Trump to win the presidency.

During Thursday's proceedings, prosecutors showed line charts illustrating the contacts between Stone and top Trump campaign officials. But that teaser of evidence was overtaken by hours of lively testimony by Credico, whose testimony is expected to continue Friday.

Prosecutors appeared to be using Credico's testimony to flesh out the details of Stone's supposed "backchannel" to WikiLeaks in 2016 and the relationship between the two men. At times, Credico was misleading Stone, then Stone was threatening Credico, according to testimony and several messages shown to the jury.

The lies about Julian Assange, the founder of WikiLeaks who had announced a cache of stolen documents that could hurt Democratic presidential nominee Hillary Clinton in 2016, started after Stone publicly said he was communicating with Assange in August that year. Credico testified that, following Stone's statement, he tried to book Assange on his radio show.

"He was a great person to have on the show," Credico said about Assange. "This would be a huge catch at my station."

He got the interview.

Later, Stone helped Credico book Libertarian presidential candidate Gary Johnson on his show too.

After thanking Stone at the time, Credico offered to help him. "What can I do as a quid pro quo, as it's going around these days," Credico called the exchange, an apparent reference to the ongoing impeachment inquiry now facing Trump.

That's when Stone asked him to get in contact with Assange so the WikiLeaks founder could appear on Stone's radio program. But Credico testified Thursday he couldn't actually make that happen.

Credico continued to mislead Stone, by implying to him he was reaching Assange about WikiLeaks' Democratic email releases.

Credico, for instance, had written an email to Stone on September 18, 2016, saying "that batch probably coming out in the next drop ... I can't ask them favors every other day. I asked one of his lawyers ... they have major legal headaches riggt (sic) now ... relax."

But Credico told the jury Thursday that he had no inside information.

During another exchange, prosecutors highlighted how Credico told Stone he had passed a message to Assange. "Had you actually passed a message to Julian Assange?" prosecutor Aaron Zelinsky asked. "No," Credico responded.

Credico also testified that when he went to London in 2016, he dropped a letter off at the Ecuadorian Embassy asking Assange to do a live radio show from inside the embassy. But Credico didn't ever get in touch with Assange, according to his testimony.

"Somebody put their hand out, like 'Thing' from 'Addams Family,' ... and grabbed the letter. But I didn't get inside the door," Credico said.

Text messages

Stone allegedly falsely told the House Intelligence Committee that Credico had been his backchannel to Assange. But prosecutors allege Stone had a different person, author and conspiracy theorist Jerome Corsi, attempting to get in touch with the WikiLeaks founder to help the Trump campaign.

In addition to being a witness who speaks to Stone's lying charges, Stone also allegedly threatened Credico, pressuring him to lie to Congress.

At one point, prosecutors showed what Stone's lawyers told the House in a letter. Yet Stone had shown Credico a different version of the letter.

A prosecutor highlighted during testimony Thursday how drastically Stone shifted his story and sent abusive texts and emails to Credico as he allegedly withheld information and documents from House investigators about his attempts to reach WikiLeaks in 2016.

Stone had actually told his associate Corsi to get to Assange in 2016, but instead told the House that Credico was his backchannel to WikiLeaks. After Stone testified on the Hill, he sent scores of emails to Credico, threatening him and peppering his texts and emails with foul and explicit language.

Credico had gotten a House subpoena in late 2017, and Stone implied he should lie to the House and told him to assert his Fifth Amendment right to avoid self-incrimination, according to testimony Thursday.

"Because of Trump, I could never get away with asserting my Fifth Amendment right," Stone told Credico, adding he believed Credico could, according to the written evidence presented at trial.

During testimony, a former FBI agent who worked on the case said Credico emailed Stone eight times between March 2018 and May 2018 insisting that it was wrong for Stone to have told the House he was a backchannel to WikiLeaks.

Over a series of text messages, Credico confronted Stone on asking him to cover Stone's alleged perjury. Credico pointed out to Stone, via text, that he wasn't a backchannel, but Stone had told the House committee he had a backchannel.

Randy Credico

Stone responded, "What the f*** is your problem. Neither of us has done anything wrong or illegal."

Credico then wrote, "You open yourself up to the six counts of perjury," according to the text messages.

"I'm getting you the best press of your life," Stone said.

Stone also suggested several times that Credico should lie to the House, invoking a character from "The Godfather: Part II" who lied to Congress in the film.

"Roger stone this, Roger stone that," Stone wrote to Credico, referencing a line from the movie. This message was sent around the time Credico had received a House subpoena and had told Stone about it. Stone then twice mentions to Credico -- with major misspellings -- Frank Pentangeli, the character from the movie who lies to Congress.

'Journalistic privilege'

During Thursday's trial, prosecutors shared for the first time audio of Stone testifying in a closed-door House Intelligence Committee interview in which he allegedly lied.

During the testimony, he flatly denied he had communications with his associates "in connection with Russian collusion." But a member of the committee reminded him that they also sought a broader range of information, anything that could relate to their investigation.

"I believe we have fully complied with your request," Stone replied. The House Intelligence Committee pressed Stone about who his "source" was who had contact with Assange, which he had discussed with Infowars founder Alex Jones, according to the audio.

When pressed by the committee, Stone cited "journalistic privilege" because his conversation with a journalist was "off the record," he said during his testimony.

"It would be better for everybody, including me, if I could tell you his name," he said. During the Mueller investigation, the House Intelligence Committee voted to provide a transcript of this interview to Mueller when he requested it.

Trump connection

It's unknown who prosecutors may call as the next witness against Stone. But several prominent former Trump campaign officials, including Steve Bannon and Rick Gates, are on deck to testify, positioning the trial to focus more in the coming days on Stone's connections to Trump in 2016.

Federal prosecutors on Thursday highlighted the volume of conversations Stone had with then-candidate Trump and other top officials from his campaign throughout 2016.

Prosecutors attempted to paint a detailed image of who Stone spoke to and when as the first witness, a former FBI agent who worked on the Stone case, wrapped up her testimony.

Stone's contacts with then-top Trump campaign official Paul Manafort spiked in April 2016, according to one chart used in court with yellow, green and blue lines depicting Stone's communications with the campaign each month. Stone's evident conversations with Trump were much less than his conversations with Manafort and Manafort's deputy Gates, but he still communicated with Trump a handful of times leading up to the election.

The chart played a relatively small role in the prosecution's rollout of evidence Thursday. Former FBI agent Michelle Taylor's testimony has focused more on Stone's alleged witness tampering -- how he threatened Credico several times over text and email -- and what he told the House Intelligence Committee in September 2017 about his supposed "backchannel" to WikiLeaks.

Laughter in the courtroom

Credico's comments from the witness box drew laughter at times from the audience and light scolding from the judge.

At one point, Credico launched into retelling the backstory of how he and Stone had a falling out around 2011, which occurred after Stone circulated a rumor that Credico had died of an overdose, he said,

"It's a big practical joke, but my friends and family did not find it a joke," said Credico.

During another exchange, prosecutors pulled up a list of impressions Credico can do, prompting Credico to offer to do some -- such as presidential candidate and Vermont Sen. Bernie Sanders -- but the judge refused.

"We know you are a comedian, but this is serious," Judge Amy Berman Jackson said.

Credico was asked if he had ever done an impression of Frank Pentangeli, the character from "The Godfather: Part II," for Stone.

"I don't recall doing Frank Pentangeli" for Stone, Credico said.

Inside the courtroom, jurors and some people in the gallery were laughing at some of Credico's responses. But Stone's party, including his wife and daughter, didn't appreciate the humor. Zelinsky, the prosecutor, was patient with Credico's bombastic answers but kept glancing at the clock when Credico would launch into a tangent.

The prosecution will call Credico back on Friday to finish his testimony. The judge dismissed the jury, telling them not to research or discuss any information about the case, "not even downloading 'The Godfather' on Netflix," she said.

CORRECTION: This story has been updated to correctly describe the charges Stone faces.