Stolen . . . or saved? Professor accuses late minister of pilfering Edward Hopper artwork now at MFA.

Hopper himself seemed to have little use for the student work, painted decades before he made his name as the 20th-century’s foremost chronicler of American solitude. He rarely painted self-portraits as a mature artist, and Hopper kept this one far from public view at his childhood home in Nyack, N.Y.

The MFA hasn’t exactly celebrated the painting, either, dusting it off for a handful of exhibitions over the years, and there’s no record the museum has displayed it with the permanent collection since the self-portrait’s arrival some 50 years ago.

This humble self-portrait, however, is enmeshed in one of the art world’s more unusual disputes. Leading Hopper scholar Gail Levin insists this painting is a prime exhibit in what she claims was a vast swindle by the late Rev. Arthayer R. Sanborn, whom she says stole hundreds of early Hopper works when he lived near the family home in the 1960s.

When it comes to Hopper’s life and work, few people are as knowledgeable as Levin. She formerly curated the Hopper collection at the Whitney Museum of American Art, home to the world’s largest collection of his art. She has written a Hopper biography, compiled his catalogue raisonné, curated numerous exhibitions, and authored several other books and articles about the artist.

But though Levin is a recognized authority on Hopper, her detective work has been less convincing to the institutions that now house his artwork.

The Whitney, which Levin says is rightfully entitled to the Sanborn-affiliated works, has declined to pursue her accusations. Similarly, the MFA curator charged with researching such claims called Levin’s assertions “a hypothesis,” adding she doesn’t see “any real red flags.”

But that hasn’t stopped Levin, who’s written voluminously about the matter on her website, from singling out the MFA’s self-portrait.

“I’m not making these accusations out of thin air,” said Levin, an art historian at Baruch College in Manhattan. “I have evidence.”

Given the Whitney’s stance, Levin said she’s not calling for the Boston self-portrait to be given to the New York museum. Rather, she wants “transparency” from the MFA, and other museums with Sanborn-affiliated work, and asserts that “nothing documents” the Hoppers ever transferred artwork to Sanborn.

“There’s no legal way he got that art,” Levin alleged. “The MFA is asking us to suspend credulity.”

The result is one of the art world’s stranger controversies: an esteemed art historian accusing a Baptist minister of pilfering hundreds of artworks and an art world seemingly indifferent to her pleas.

Garrulous in public, Sanborn spoke often of his close relationship with the Hoppers. He once told an audience he’d had his own key to the family home in Nyack, where he found a “treasure trove” of Hopper’s belongings in the attic. His reason for the house key: The minister looked in on Hopper’s ailing sister, Marion, caring for the house after her death in 1965. He also tended to the artist’s widow, Josephine, who lived alone in the couple’s Manhattan apartment after Hopper’s death in 1967.

But when Josephine died the following year, she did not leave any art to Sanborn. Rather, she bequeathed nearly all of Hopper’s artwork to the Whitney, which subsequently hired Levin to oversee the vast collection. (The widow did identify Sanborn as one of six beneficiaries to split the rest of the estate once its other obligations were fulfilled.)

Nevertheless, Sanborn accumulated a huge Hopper collection: Last year, The New York Times identified more than 300 works once owned by Sanborn. Levin puts the number closer to 1,000, including the self-portrait now at the MFA.

Sanborn, who died in 2007, said he received many of them as gifts from the Hopper family, including from the artist’s sister, Marion, while she lived in the family’s Nyack home, now known as the Edward Hopper House Museum & Study Center.

“A lot of it was verbal,” said Sanborn’s daughter, Ann Bach. Marion “gave my father permission to go into the house.”

But Levin says there’s no record the Hoppers authorized Marion to give the artworks away. She adds that there’s no documentation that the Hoppers ever gave the minister anything more than a single reproduction of a painting by Edward.

The Hoppers were “obsessive,” said Levin, who recalled that Sanborn first approached her at the Whitney to get some of his works included in the catalogue raisonné. “They made it very clear: They recorded it, they inscribed it. Yet Sanborn gets hundreds of artworks with no notes, no records, no inscriptions? Why is he different? I don’t believe it.”

So, if Josephine Hopper’s will directed all of Edward’s work to the Whitney, and there’s no record the couple ever gave art to Sanborn, how did the self-portrait end up at the MFA?

The answer, said Levin, is simple.

“Sanborn was in the attic,” she said. “He says he made his collection in that attic.”

Victoria Reed, the MFA’s senior curator for provenance, said she has reviewed what Levin’s put forward as evidence and found it wanting.

“I think it’s inconclusive,” said Reed. “I don’t know how you would prove her allegations.”

Meanwhile, the Whitney, which received more than 3,000 works upon Josephine’s death, established the Sanborn Hopper Archive in 2017 following a family gift of some 4,000 objects.

“The Museum is aware of decades-old claims that it was entitled to additional pieces,” the museum told the Globe in a statement. “The Museum has found no basis to pursue the matter and considers the issue of Hopper’s estate closed.”

Complicating matters, the Whitney fired Levin in 1984, accusing her, she said, of publishing a Hopper book without authorization. Levin believes she was dismissed for voicing concerns about Sanborn. The museum said it could not comment on personnel issues.

Levin’s broader allegations have divided the small field of Hopper studies.

Carter Foster, a former curator at the Whitney who helped secure the archival gift, recalled how Levin approached him at an event for last year’s Hopper show at the museum.

“She was like, ‘Are you going to be on the right side of history?,’” said Foster, who described the allegations as “ancient history.” “I think I’m on the right side of history because I helped get this archive to the Whitney.”

But Vivien Green Fryd, an emerita art historian at Vanderbilt University, called Levin a meticulous scholar “who goes deep into the archive to find information that others haven’t found.”

“There’s no clarity about how [Sanborn] got the material,” said Fryd, who’s also written a book on Hopper. “I find that troubling.”

According to the MFA, the Rev. William H. Brittain and his wife, Katherine, first approached the museum with the self-portrait in the mid-1970s. The couple, who lived in Dedham, eventually produced a letter from the minister, who said Hopper’s sister gave him the painting before her death.

There “was no family left with the exception of her brother Edward Hopper who had no interest in these early works,” Sanborn wrote in a letter dated August 1976. He added that he’d been friends with the Brittains for many years, and since “Mrs. Brittain is an artist I knew of her interest in Hopper and so gave them this picture.”

The museum ultimately purchased the painting for $27,500, or roughly $147,000 today.

Levin, whom the MFA asked to consult on the work before the acquisition, is now convinced she was unwittingly involved in an illegal transaction.

“I was used to authenticate it in my first two months on the job,” she said. “I didn’t realize at the time that I was facilitating the sale of something without clear title.”

Levin has publicly written that Brittain, a fellow minister, was “a fence” for Sanborn.

But Brittain’s daughter said her father and Sanborn became lifelong friends after attending seminary together. She recalled how Sanborn gave them the self-portrait during a holiday visit in the late 1960s.

“My parents had the Hopper on the living room wall,” said Framingham’s Karen LaRosa, who added they sold it to help fund their retirement. “They put it in an investment so they could live.”

Levin remains skeptical.

“Why, if Marion owned a certain number of works, didn’t Hopper and Jo record them?,” she asked, using Josephine Hopper’s nickname.

The MFA’s Reed said that although the museum did not independently verify the gift, Sanborn’s letter is “the best information we have” for the painting’s provenance.

“I don’t know that there’s any indication there of theft,” said Reed, who has presided over several high-profile returns. “We would need more evidence.”

She added that Sanborn’s signed letter, the foundational document describing the painting’s chain of custody, may have constituted due diligence in the 1970s, but the museum would likely ask for more information today.

“We always try to verify verbal and signed statements,“ she said. “If we can’t verify it, then we have to ask why not.”

Malcolm Gay can be reached at malcolm.gay@globe.com. Follow him @malcolmgay. Emily Sweeney can be reached at emily.sweeney@globe.com. Follow her @emilysweeney and on Instagram @emilysweeney22.