"Portrait of a Rabbi," the painting recovered early this year after being stolen from San Francisco's de Young Museum more than 20 years ago, has undergone more than a mere facelift.

For one, the work that had historically been attributed to the famed Dutch artist Rembrandt has now been ruled an imitation.

Perhaps even more ignominiously, the painting has been renamed "Portrait of a Man with Red Cap and Gold Chain."

According to museum officials, the work, stolen in a 1978 Christmas Eve robbery, had suffered from a lot of neglect during its travails since the robbery. Adverse weather conditions, coupled with a botched attempt to clean the painting's surface, left the piece with several blemishes.

And although museum officials say that the damage to the work is treatable, the damage to the painting's reputation is not.

"At this point, the painting's value is in somewhat of a downward spiral," said Steven Nash, the associate director and chief curator of Fine Arts Museums of San Francisco, which runs the de Young and other museums.

According to Nash, the Netherlands-based Rembrandt Committee has been pouring over photos of the missing work for the past decade.

The conclusion: The painting was probably the work of one of the Dutch master's students, and the subject can't be authenticated as being a rabbi.

The painting, which was exhibited at the de Young Museum several months ago, along with two other works that were stolen, is not scheduled for any more public shows.

"At this point, we're looking at the work as a possible period piece," said Nash. "But there are no plans to display it again any time soon."

Even if "Portrait of a Man with Red Cape and Gold Chain" doesn't cut it as an authentic Rembrandt, the Dutch master still has few peers when it comes to painting Jewish subjects.

Rembrandt, who lived from 1606 to 1669, was responsible for many well-known works with Jewish content. For many years, the artist lived near the Jewish quarter in Amsterdam; many Sephardic Jews who fled persecution in Spain and Portugal were his neighbors.

Among them were Ephraim Bonus, a physician and poet who was the subject of both a painting and etching by Rembrandt, and the influential scribe Rabbi Manasseh ben Israel.

Curiously, even though Jews constituted only slightly more than 1 percent of Amsterdam's population, scholars have estimated that almost one-fifth of Rembrandt's male subjects were Jewish.

According to Larry Silver, professor of art history at the University of Pennsylvania, Rembrandt was heavily involved in building bridges between Christians and Jews.

"But that may have been due to his desire to hasten the arrival the messiah," Silver said.

Rembrandt biographer Franz Landsberger said, "The Jewish fate, insofar as facial expression has ever mirrored it, has never been represented with such authenticity and such grandeur as in Remrandt's Jewish portraits."