PAINT ROCK, Ala. — At a senior center here in the northeast corner of Alabama, one decree ordinarily rises above the rules of Rook and dominoes: No talking about politics or religion. But by late this week, after days of watching President Trump excoriate and belittle Attorney General Jeff Sessions, some seniors were ready to let the rule slide so they could defend an Alabamian.

“I think everybody’s been a little aggravated,” Wilma Counts, a retired seamstress who has voted for both men, said before a lunch of smoked sausage, sliced peaches and yellow cake. “I want Trump to stay because I think he’s got some good ideas, but I don’t like him picking on Sessions.”

Alabama may adore Mr. Trump, but this is a state that first loved Mr. Sessions.

And to a striking degree in a state where Mr. Trump won 62 percent of the vote last fall, Republicans and Democrats alike have closed ranks around Mr. Sessions, who was the state attorney general before he won a Senate seat four times and joined the president’s cabinet. Interviews with voters from four counties, three of which supported Mr. Trump, revealed near-absolute confidence in Mr. Sessions’s virtue and conservatism, a swelling of state pride and, in this case at least, an encroaching skepticism of the president.

In Montgomery, the capital, Perry O. Hooper Jr., a former state legislator and a co-chairman of Mr. Trump’s campaign in Alabama, said, “Jeff Sessions is a man of great character and integrity, he’s a good man, and he is the king of the hill in Alabama.’’

Senator Richard C. Shelby might dispute the last part of Mr. Hooper’s assessment, but Mr. Sessions was a seemingly immovable, if surprisingly low key, political force in Alabama during his decades in elected office. After his Senate campaign in 2008, you could drive for more than 150 miles from here without entering a county Mr. Sessions lost. In his last campaign, in 2014, he had no Democratic or Republican opposition despite years of tangling with liberals and centrists.

Virtually no one in Alabama, including Mr. Sessions, thought he would ever ascend beyond the Senate seat he most likely could have held as long as he liked. Then Mr. Trump was elected president and chose Mr. Sessions for attorney general, only to see him recuse himself from the inquiry into Russian meddling in last year’s election.

The decision infuriated Mr. Trump for months, but only on July 19 did he begin a sustained campaign of public complaints about the attorney general.

In an interview with The New York Times, Mr. Trump complained that Mr. Sessions “should have never recused himself” from the Russia investigation, and he said he would not have nominated the senator if he had known his plans. And on Twitter, he questioned Mr. Sessions’s leadership of the Justice Department, described the attorney general as “beleaguered” and vented that he had been “VERY weak.”

Mr. Sessions, 70, who rose in elected office after a nomination to a federal judgeship collapsed amid misgivings about his views on race and civil rights, has said he does not plan to resign. He told Fox News that Mr. Trump’s Twitter posts were “kind of hurtful, but the president of the United States is a strong leader.”

He continued, “He is determined to move this country in the direction that he believes it needs to go to make it great again.”

But the clash has clearly strained Mr. Trump’s ties to some conservatives in Alabama and beyond. For voters wary of Mr. Trump’s conservative bona fides or personal conduct, Mr. Sessions, the first senator to back the New York developer’s presidential campaign, has been something of a guarantor and a backstop.

“I voted for Donald Trump not because I liked or trusted Donald Trump; I voted for Donald Trump because I trusted Jeff Sessions and Jeff Sessions voted for Donald Trump,” said Donna Horn, the chairwoman of the Pike County Republican Party in southern Alabama.

“I will find it impossible to work for Donald Trump if he continues to malign Jeff Sessions,” said Ms. Horn, who once allowed Mr. Sessions to hold a meet-and-greet in her living room.

The topic has resonated from cafes to spin classes.

“Jeff Sessions is the best man in the United States, and they don’t make no better than him,” Ann Clark, who used to run an Army surplus store, volunteered as she worked on a Times Square jigsaw puzzle at the senior center in Paint Rock, population 205.

If she had to choose between Mr. Trump, a man she said she trusts “100 percent,” and Mr. Sessions, she unhesitatingly said she would pick the attorney general.

Mr. Trump’s approach to Mr. Sessions has only somewhat dented his support in Alabama, and few people here think that Mr. Trump would be at serious risk of losing the state if he sought re-election in 2020. But voters who stood by Mr. Trump during previous controversies said the battle over Mr. Sessions had given them sudden pause. And any sympathy for Mr. Trump’s treatment of Mr. Sessions seemed mostly rooted in the legal reality that Mr. Sessions serves at Mr. Trump’s pleasure.

“Well, Trump is president,” Wesley Juron, 23, said in Huntsville, just west of Paint Rock. “I like to see an Alabama guy up there, but one is president and one is attorney general. One can fire the other.”

Alabama’s largely powerless Democrats were generally reluctant to join the pro-Sessions lovefest, but they also did not criticize him as harshly as Mr. Trump did.

In Huntsville, State Representative Anthony Daniels, the Democratic leader in the Alabama House of Representatives, said residents in his district were “not tuning in to this political reality show,” but he expressed concern about whether Mr. Sessions could be an effective leader of the Justice Department.

“This is not an endorsement of Jeff Sessions, let me be very clear, but being an Alabamian and a leader in this state, I expect leaders to act accordingly and display a certain decorum,” said Mr. Daniels, one of the most prominent black politicians in the state. “I also expect leaders to allow the folks that they hire to do their jobs. I would say to the president: Let the attorney general do his job.”

At Mud Creek Outdoors in nearby Gurley, where the couches are camouflage and Lady the bloodhound greets visitors at the entrance, Danny Hill, 66, sat at the counter, declared himself a supporter of both Mr. Trump and Mr. Sessions and wondered aloud how, exactly, the president and the attorney general had emerged at such odds with each other.

Then, as so many other people in Alabama did, he counseled caution by Mr. Trump.

“Chill out. Chill out,” Mr. Hill said. “Smoke one if you’ve got to.”