The bank sign flashes "Free At Last" and a woman hurries along Main Street here carrying an armful of yellow ribbons. But in the old courthouse down the block by the Civil War memorial, the patients of Iranian-born Dr. Parviz Modaber are aroused by something other than the return of the American hostages.

"Wherever he goes, I'll go," an angry Sue Snyder says of Modaber, a 50-year-old gynecologist. "When you see him you don't go to anyone else."

The doctor, barred last fall from using this small town's only hospital, has accused hospital officials of trying to ruin his medical practice in anger over the seizure of the hostages in Tehran.

The hospital contends that Modaber, who received his medical education in Germany and served three years' residency in Virginia, needs more medical training.

While townspeople flood the local newspapers with letters on the controversy, Modaber finds himself at the center of a bitter fray that has directly touched dozens of the nearly 10,000 inhabitants of this farming community 60 miles southwest of Washington.

A naturalized American citizen who came to Culpeper nearly five years ago, Modaber has filed a discrimination suit against hospital officials. The chubby, dark-skinned physician says it is more than a coincidence that his career troubles start after the takeover of the American embassy.

"I left Iran 27 years ago because of this kind of kangaroo court, but I promised my patients that I would stay and make a stand until justice prevails," Modaber said this week after his lawyers unsuccessfully sought to postpone the loss of his hospital privileges.

Culpeper Memorial Hospital revoked Modaber's access to its surgical and obstetrics facilities Nov. 12. He was advised by letter to take another year of postgraduate work, with an emphasis on genecological surgical procedures and the medical management of geynecological infection. Modaber, one of three gynecologists in the town, was able to stave off enforcement of the revocation until Wednesday, when a Culpeper Circuit Court judge ruled that the doctor cannot use the hospital until his case is decided. A hearing has been set for April 21.

In the meantime, Modaber claimed in court testimony, his practice could be "destroyed" while he waits to have his name cleared.

"I can't do any obstetrics, only check ups." Modabar argued. "If a mother has a delivery or an emergency, there's no way I can help her."

The dispute, he said, has caused his patient load to drop by 60 percent. In addition, he says his attempts to affiliate with another hospital were rebuffed "because of the charges hanging over my head."

The criticisms of Modaber, however, have failed to mute an outpouring of praise for him by his patients. Many have turned their anger against the hospital for turning against the doctor.

"I called another doctor when I was seven months pregnant and having trouble, but the doctor wouldn't come," complained Pat Winters, now a patient of Modaber. "Why didn't the hospital say anything about that?"

Patients call Modaber kind, conscientious and capable. They contend that other doctors at the hospital are jealous because Modaber's popularity has lured away their clients. Letters to the editor of the town's newspapers called Modaber the best gynecologist in Culpeper and criticized the hospital for putting him through "such a terrible ordeal." One, Elizabeth Elston, wrote that Modaber's difficulties with the hospital were the result of prejudice "because he was born an Iranian."

Hospital officials called in a Lynchburg gynecologist last week to buttress their claim that Modaber's continued use of the hospital would endanger patients.The Lynchburg doctor, based on a review of Modaber's patient charts, called Modaber's care "substandard." But a Georgetown University gynecologist disputed that testimony, and Modaber's attorneys argued that the Culpeper problem arose from the "inability of professionals to interact."

In pressing his contention that the turmoil in Iran triggered his Culpeper troubles, Modaber argued that hospital officials allowed him to practice there for years and had renewed his permit as recently as last March.

When officials began raising questions about the way he kept his medical charts and his use of certain medications and Caesarean section delivery procedures, Modaber said he asked for a review by an independent health agency. This was denied.

"I don't mind having my patient care reviewed, but they seem to be looking for something to find wrong," Modaber complained. "And the problems that other doctors have are never mentioned."