Authorities found the naked, towel-draped body of Allyson Bergmann on a sofa bed in her parents' living room. The 9-month-old girl's head was tilted and stiff, her eyes half open and fixed, her brown hair still wet from the bath her mother had given her.

Feverish since May 28, Allyson had become more lethargic over the next 10 days -- too sick even to cry. On June 7, she died of pneumonia and bacterial meningitis without having seen a doctor. Her parents, David Bergmann, 28, and Kathleen Bergmann, 27, thought she was teething.

On Sept. 11, the Bergmanns were convicted of reckless homicide and child neglect. They will be sentenced Oct. 29 and could face up to 28 years in prison.

Last week, a judge sentenced another northeast Indiana couple -- Gary and Margaret Hall -- to five years in prison for refusing to seek care for their 26-day-old son. The baby died in his father's arms of untreated pneumonia.

Mrs. Hall, 27, told the court that she would again refuse medical attention for her children. "On the basis of my convictions, and of my fear of God Almighty, I could not provide medical care," she said.

The Bergmanns and the Halls are members of the Faith Assembly, an Indiana-based religious sect that shuns doctors and hospitals. Their convictions and probable appeals are focusing national attention on the clash between freedom of religion and the state's responsibility to protect lives.

The trials also have focused attention on Faith Assembly and on published reports that as many as 88 of its members or their children have died from treatable illnesses or injuries. A federal-state study of 20 of those deaths in two Indiana counties concluded that the mortality rate for sect newborns was three times higher than the statewide rate and that the rate of maternal deaths was 100 times higher than the statewide rate. Religious Exemption

Like many states, Indiana has a religious exemption in its child neglect law. The exemption states, "It is a defense that the accused person, in the legitimate practice of his religious belief, provided spiritual treatment through prayer, in lieu of medical care, to his dependent."

The Bergmanns, conducting their own defense and calling only themselves as witnesses, invoked that exemption in their trial. They contended that they were not negligent because they prayed for their daughter and held a 24-hour-a-day vigil, and her father fasted for four days.

"I thought she was teething," Kathleen Bergmann said. "I didn't realize it was that serious. If I had, I probably would have prayed in that direction."

David Bergmann, placing a Bible on a wooden rail in front of him, quoted passages of it in his testimony: "If there are any sick among you, call the elders, and they will anoint them with oil, and they will be healed."

Kathleen Bergmann, who is about six months pregnant, testified that the couple's faith was unshaken by the baby's death. "Had we feared and doubted God, we would have lost her anyway," she said.

Dr. John S. Ramsey, the Noble County coroner, testified that the baby had a 90 to 95 percent chance of surviving with timely medical treatment -- and no chance without it. He told the jurors that the most striking feature of the autopsy was the baby's brain, layered with a membrane of dead white blood cells.

"We don't see bacterial meningitis this far advanced in the 20th century," he said.

Prosecutor G. David Laur argued that the Bergmanns' defense didn't apply because withholding medical care from a sick child is not a legitimate practice of religion. "Religious practice ends where the sacrifice of innocent children begins," he told the jury.

Whitley County Circuit Judge Edward J. Meyers, in sentencing the Halls in the second case, agreed: "Certain societies have now reached a point where we can't tolerate human sacrifice in the name of religion."

Faith Assembly is a rapidly growing sect that started about 20 years ago in the basement of its founder, the Rev. Hobart Freeman. Its membership is predominantly white and well-educated and its families include many young couples with children.

Freeman refuses to talk with reporters. But a good deal is known about him from his books, biographies, school and seminary records, tapes of his sermons and interviews with friends and former Faith Assembly members.

Freeman, 64, lives with his wife June in a remote northern Indiana home and enjoys solitary hobbies such as long drives and ham radio.

Freeman's CB handle, Overcomer, is a Faith Assembly term for a Christian who triumphs over severe spiritual trials. A native of northeastern Kentucky, he was stricken with polio as a child and has a pronounced limp. He moved to St. Petersburg, Fla., and for a time owned a grocery store and worked part time as a photographer.

In 1952, Freeman was "born again" at a revival service and gave up his store and studio.

Freeman then launched his religious education, receiving a doctorate in theology from Grace Theological Seminary in Winona Lake, Ind. There he taught Hebrew, philosophy, ethics and the Old Testament until he was fired in 1963 because, according to a statement by seminary President Homer A. Kent, "his views did not coincide with those of the seminary."

Former sect members say Freeman has talked from the pulpit about his dismissal, attributing it to differences over several religious issues -- particularly his belief that Christians shouldn't celebrate such holidays as Christmas and Easter because they are rooted in pagan rituals. Another issue, Freeman reportedly has said, was that he had founded a church in his basement. High-Pitched Sermons

Over the next 15 years, Freeman's congregation moved into a garage and later into a halfway house for alcoholics and drug addicts called the Glory Barn. In 1978, Freeman built his own church in a cornfield near Wilmot, a small village between South Bend and Ft. Wayne.

In this 31,500-square-foot building of corrugated metal walls and a slab floor, Freeman preaches. He rouses his congregation, numbering as many as 2,000, with high-pitched sermons laden with homespun humor and Biblical references.

Forty of Freeman's ministers have established satellite churches in a dozen Indiana cities, in at least 21 other states, including Virginia, and in eight foreign countries. The message is spread still further by a nationwide cassette tape and publishing ministry.

Faith Assembly frowns on television, movies, newspapers, magazines, dancing, alcoholic beverages, involvement in government, birth control and sexual foreplay. But it is the sect's view on medical care that has fueled the furor.

Freeman tells his followers to shun medicine, hospitals and doctors and to rely on their faith for healing. In a 1981 sermon, he preached, "The word of God is clear about divine healing. The prayer of faith will heal the sick. Lay hands on the sick and they will recover."

Other churches, of course, believe in faith healing or have taboos regarding medical care. Jehovah's Witnesses, citing the Biblical prohibition against eating blood, refuse transfusions, and Christian Scientists, considering illness illusory, rely on practitioners trained in the use of prayer and positive attitudes.

To Freeman, seeing a doctor shows lack of faith. Faith conquers all, he preaches. Sect members give birth at home, discard eyeglasses and hearing aids, cancel life insurance policies and don't wear seat belts -- all in the name of faith. Some followers have even tried to pray the dead back to life. Investigations

In May 1983, the Indiana State Board of Health began taking note of reports of "excessive perinatal and maternal mortality in northeastern Indiana possibly due to medical neglect."

"Approximately 40 Indiana deaths and 52 Midwestern deaths were said to have occurred over the past eight years in a religious group known as Faith Assembly, a large fundamentalist church which shuns all medical attention in favor of 'spiritual' healing," it said in a subsequent report.

The information about the deaths had come from stories by this reporter and another, published in the Fort Wayne News-Sentinel. Citing police and coroner reports, other documents and accounts by eyewitnesses, the stories had reported 52 instances in which Faith Assembly members and their children had died from treatable illnesses and injuries.

Responding to those reports, the board of health, joined by the federal Centers for Disease Control, investigated the deaths that occurred in Kosciusko and Elkhart counties, where most of the sect's Indiana members live. (The sect's precise membership "could not be determined as leaders of the church declined to respond to fact-finding efforts," the investigators later reported.)

The joint study concluded that for sect members in the two counties, the perinatal death rate (stillbirths and deaths within 28 days after birth) was three times as great as the statewide rate and the maternal death rate (deaths related to pregnancy and occurring up to one year after termination of pregnancy) was about 100 times as great as the statewide rate.

In an interview, one of the authors of the study, Dr. Craig Spence of the board of health, said that in his opinion the "chances of surviving would be overwhelming in many of those cases."

After the Fort Wayne newspaper provided information about the 52 deaths for the joint study, it reported in other articles 36 more instances of Faith Assembly deaths from treatable illnesses or injuries. The 88 reported deaths occurred in over 11 years and in 11 states -- Indiana, Ohio, Michigan, Illinois, Iowa, Kentucky, Missouri, Massachusetts, Louisiana, Arizona and Wisconsin.

As Faith Assembly grows, school officials have noted that sect parents are increasingly removing their children from public schools to tutor them at home -- making it difficult for officials to monitor the health of children and get court-ordered medical care if necessary.

"I'm afraid of what's happening to the children whose parents are members of the church," said Kosciusko County public health nurse Barbara Clouse. "They're not getting their immunization for polio and measles, diphtheria and tetanus . . . . They're not wearing the glasses that are prescribed for them . . . . They see no dentist."

The 88th death reported by the newspaper was a 15-year-old girl who was removed from school by her parents almost four years ago. Her death in September from kidney failure is being investigated by a grand jury. Immunity Laws

Ten years ago the federal Department of Health, Education and Welfare issued regulations requiring states to pass religious exemptions to their child protection laws or risk losing federal funds for child protection programs. In 1983, HEW's successor, the Department of Health and Human Services, dropped the requirement. But by then 42 states and the District of Columbia had passed some sort of exemption for spiritual treatment.

Rita Swan, founder of the Iowa-based Children's Healthcare Is a Legal Duty, Inc. (CHILD), said the Bergmann and Hall convictions would make people "recognize the injustice they're doing to parents by giving them the impression, through these immunity laws, that parents have a religious right to deny children medical care."

The authors of the federal-state report -- Spence, another doctor from the board of health and one from the CDC -- said the question of "spiritual" treatment of seriously ill adults "will always remain a fundamental personal choice." But they added:

"What constitutes medical neglect of dependent children? At what point do parents have the privilege to deny their offspring contemporary treatment which could spare a suffering infant or child disability or death?

"Such questions deserve further discussion, not only as a dynamic, social concern, but as a public health issue as well."