The Rev. Lawrence M. Jenco was kept chained to a wall for the first six months of his captivity in Lebanon and was moved to seven different locations by the Moslem fundamentalist extremists who held him, a brother of the newly freed American priest reported today.

As Jenco was reunited with members of his large family at the U.S. Air Force Medical Center here, details of his nearly 19-month ordeal began to emerge, relayed by relatives.

"He was never tortured, never beaten -- no brainwashing type of thing," said John Jenco, the brother. "He was just chained with a ring around his ankle to the wall with a piece of chain."

The priest was released from the chain last July, when he was transferred into a four-by-five-yard cell with four other U.S. hostages, his brother said.

His captors gave him a Bible and a set of rosary beads. "I said 25 million Hail Marys and rosaries" and also tried to exercise in the cell, Jenco was quoted as saying.

John Jenco said his brother told him the hostages were allowed to bathe once a day and had only two pairs of underwear -- "one for washing and one for wear" -- and that they "were strictly in their underwear the whole time."

The 51-year-old Roman Catholic clergyman, from Joliet, Ill., was turned over to U.S. officials Saturday in Damascus, Syria, after being freed in Syrian-controlled eastern Lebanon by his Islamic Jihad captors.

When he was flown to the medical center here for examination and debriefing, 10 of his relatives -- three brothers, three sisters, a nephew and three in-laws -- flew to West Germany for a joyful reunion.

After the two-hour reunion, Jenco, wearing slacks and an open-neck shirt, spoke with reporters and expressed concern for the release of the others, including at least three Americans, still held as hostages in Lebanon.

Appearing on the hospital balcony, festooned with American flags, he declared in a soft voice, "I hope to come back to this balcony soon for Terry Anderson, David Jacobsen and Thomas Sutherland."

They are three of the four Americans with whom Jenco shared a cell during part of his captivity. The fourth was the Rev. Benjamin Weir, a Presbyterian minister from Berkeley, Calif., who was kidnaped in May 1984 and freed last September.

Jenco said that he never saw the other missing American, William Buckley, a political officer at the U.S. Embassy in Beirut who was captured in March 1984 and whom Islamic Jihad reported killing last November. His body has not been found.

When asked how he felt, Jenco replied, "I realize I have the dignity of a person again, and that's a good feeling to have."

"He has forgiven his captors," said Andy Mihelich, a nephew. "He has no hate for anyone."

Family members said that the priest has been invited by Pope John Paul II to come to the Vatican on his way home to the United States but that plans have not yet been made.

Jenco's relatives, most of them from Joliet, arrived here aboard a U.S. Air Force C141 Starlifter transport plane, bringing as presents clean clothes; popcorn, his favorite snack; and gin for martinis. According to John Jenco, his brother's martini recipe is "just straight gin with his apostolic blessing on it."

Later, Mihelich said of his uncle's condition: "He is a weak man. He was very fragile and very emotional. It did not take long before tears came to all our eyes."

"He wants good old-fashioned cooking," said another brother, Joseph.

Asked if the priest knew the identities of his captors, his brother John said, "He never saw their faces because they the hostages were completely blanketed at all times when the captors were in their presence."

The priest did not know he was to be released, his brother said, but was simply taken blindfolded from his cell, driven to a spot in the Bekaa Valley and told to start walking.

Along his walk, "he had seen a couple of persons," said Jenco's brother, "but was apprehensive in making contact for fear he would be kidnaped again. So he just kept walking.