Former House Speaker John Boehner seems to be enjoying his retirement—and wouldn’t you, after what he went through in Washington? One reason for his buoyant mood, besides the chance to cut grass, is the opportunity to stay far, far away from Senator Ted Cruz.

Asked about Cruz during an appearance at Stanford University on Wednesday, Boehner called him “Lucifer in the flesh,” according to the The Stanford Daily.

“I have Democrat friends and Republican friends. I get along with almost everyone, but I have never worked with a more miserable son of a bitch in my life,” Boehner added. He said he would not vote for Cruz in a general election, though he would vote for his fellow tangerine-tinted Republican Donald Trump.

It’s not news that Boehner doesn’t like Cruz, whom he has previously called a “jackass” and a “false prophet,” nor is the source of their bad blood a mystery: Cruz helped rally revolts against leadership, particularly in the House, that led to the 2013 government shutdown, and his attempts at undermining Boehner made the speaker’s life impossible, eventually driving him to retire. Temperamentally, they’re opposites, too—the sentimental, irreverent, wine-loving Ohioan and the sanctimonious, ambitious Texan.

Boehner’s comments come at an interesting time in the presidential campaign, and they seem to illuminate the moment. Earlier in the race, Republicans who’d encountered Cruz hated him so much that they seemed to prefer Trump. (“Why do people take such an instant dislike to Ted Cruz? It just saves time,” one quipped to Frank Bruni.) Then Trump went a little too far for their tastes, right around the time of his flirtation with David Duke, the white supremacist and former KKK leader, and they started to uneasily slouch toward Cruz.

The limitations of that embrace have become clear. While it seemed likely a couple weeks ago that Trump would fall short of what he needed to clinch the GOP nomination, producing a contested convention—O brave new world, in which such chaos is Republican leaders’ fondest hope!Trump’s April 26 Northeastern sweep has shifted the ground. The entertainer now has the nomination nearly within reach. Cruz has resorted to Hail Mary strategies, including  naming Carly Fiorina his “running mate” on Wednesday—a remarkable move, given that Fiorina was herself a weak candidate; that Cruz is highly unlikely to win the nomination; and that even if he captured it at convention, he might not be able to pick his running mate.

Boehner’s comments show why Cruz’s attempts to rally the Republican Party have been futile, even though his opponent is a widely loathed misogynist, ex-Democrat, loose cannon, and race-baiter. Not everyone is willing to be as blunt as Boehner, but other GOP leaders’ feelings are no secret. (Boehner said he golfs with Trump and called him a “texting buddy,” while he offered somewhat fainter praise for his fellow Ohioan John Kasich.)

The problem is that many top Republicans have already written off this presidential race, expecting that Hillary Clinton will win the White House. Amid such resignation, there’s no incentive for them to back the man they’ve served with and despise. It isn’t so much that the top GOP figures are backing Trump; he still has barely any endorsements from officeholders, and Trump’s base is an entirely different group of people. Instead, they’re just backing away slowly. Better to quietly avert your eyes from the devil you don’t know than embrace the devil you do.