Former House Speaker John Boehner made it clear where his presidential primary loyalties lie Wednesday night, lashing out at Texas Sen. Ted Cruz as 'Lucifer in the flesh' and a 'miserable son of a b***h.'

Cruz fired back Thursday in Indiana, complaining that Boehner 'let his inner Trump come out,' and saying the two men don't know each other at all.

Cruz, who trails multibillionaire Donald Trump in the chase for the Republican nomination, has been described as a polarizing figure in the U.S. Senate. Just six of his 53 GOP colleagues in the upper house of Congress have endorsed him.

Boehner, who retired at the end of September, spoke at a Stanford University Speakers Bureau event.

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FIGHTING WORDS: Former Speaker of the House John Boehner has no love for Texas Sen. Ted Cruz, calling the presidential hopeful 'Lucifer in the flesh' and a 'miserable son of a b***h'

POLARIZING: Cruz is running in second place to Donald Trump and has only persuaded six of his 53 Republican Senate colleagues to back him. He fired back at Boehner on Thursday

LUCIFER: The prince of darkness was depicted in this 16th Century stained-glass 'The Torment of Saint Anthony' in a French monastery

The Stanford Daily reported that Boehner made a face at the first mention of Cruz, drawing laughs from his audience.

'I have Democrat friends and Republican friends. I get along with almost everyone,' he said.

'But I have never worked with a more miserable son of a b***h in my life.'

Cruz fired back during a press conference in Fort Wayne, Indiana, claiming that 'I've never worked with John Boehner.'

'Truth of the matter is I don't know the man. I've met John Boehner two or three times in my life,' he said. 'If I have said 50 words in my life to John Boehner, I'd be surprised.'

'I've never had any substantive conversation with John Boehner in any respect.'

But The Washington Post reported in 1998 that Cruz acted as Boehner's attorney when the former speaker was the chairman of the GOP conference and engaged in a nasty spat with Rep. Jim McDermott of Washington.

Boehner says he hired Cruz when he decided to sue Rep. Jim McDermott for allegedly violating wiretapping laws.

Boehner even made reference to the lawsuit during an appearance on the 'Tonight Show,' then hosted by Jay Leno, after Cruz rocketed onto the political scene as a firebrand Republican who regularly made GOP leaders sweat.

The Texan is known in the House of Representatives as a Senate interloper who helped right-wingers in the House Republican caucus band together to stand up against Boehner during a series of budget fights – including one that resulted in a partial shutdown of the federal government.

'During the government shutdown I reached out to John Boehner and I offered for [Senator] Mike Lee to come over and work with the speaker,' Cruz said Thursday.

'John Boehner's response was: I have no interest in talking to you.'

SMARTPHONE: Donald Trump texts with John Boehner often, the former House Speaker said

IT'S COMPLICATED: Boehner said his relationship with fellow Ohioan John Kasich takes a lot of work, but he still loves the man

He told a TV audience watching the press conference that Boehner's 'Lucifer' comment should offend his base of supporters.

'When John Boehner calls me Lucifer, he's not directing that at me. He's directing that at you,' he said.

'What Boehner is angry with me for is not anything I've ever said. You know, I haven't said much of anything to him. What Boehner is angry with me for is standing with the American people, is energizing and encouraging House conservatives to stand with the american people and actually honor the commitments we made.'

'You know, I will say this: If you're wondering who actually has stood up to Washington, I think John Boehner has made it crystal clear,' Cruz said.

He also hammered Trump as an 'establishment' tool, saying he 'gave John Boehner's super PAC $100,000 just a few years ago.'

White House Press Secretary Josh Earnest squirmed as he was asked about the former speaker's comments about Cruz on Thursday afternoon.

'Speaker Boehner was speaking based on his own experience,' Earnest told a reporter who asked if the White House thought Boehner's comments were helpful or harmful.

'I don't know that he was looking to be helpful or harmful. I think he was looking to be honest about his own view,' he said.

Earnest declined to weigh in on the appropriateness of Boehner's remarks, saying after a few pauses marked with 'uhhh' and 'umm': 'If you're looking for somebody to come to the defense of one Republican who's being attacked by another, you should probably ask somebody else.'

Boehner cited Trump Wednesday night as an example of a Republican with whom he has a good working relationship.

The two have golfed together for 'years' and are 'texting buddies,' Boehner said, adding that he would vote for him in November if he were the GOP's standard bearer

His friendship with Ohio Gov. John Kasich, the third leg in the Republican party's primary stool, 'requires more effort on my behalf than all my other friends,' Boehner conceded.

'But he's still my friend, and I love him.'

Boehner and Kasich worked closely together on Capitol Hill for years when Kasich was chairman of the House Budget Committee beginning in 1995.

No broadcast video was mad of the event, a fact that led moderator David Kennedy, a Stanford professor, to urge frankness from the former speaker.

Boehner, a devout Catholic, has called Cruz 'Lucifer' before. He used that term, along with 'jackass,' to describe the senator last month during a Florida appearance at a Futures Industry Association conference.

He said then that he would only back a presidential candidate who could wrap up the nomination without a nasty floor fight during the Republican National Convention in Cleveland, scheduled for mid-July.

'If we don't have a nominee who can win on the first ballot, I'm for none of the above,' said Boenher.