ANGOLA, La. » Like most of his fellow inmates, Daryl Walters, 45, can expect to spend the rest of his days in the infamous prison on a former slave plantation here. He was sentenced to life without parole for a murder more than 20 years ago in a state where a life sentence means just that.

Yet there he was on a recent evening, preaching the Gospel to 200 men in a spired church in the heart of the Louisiana State Penitentiary, talking salvation and joy to murderers and rapists and robbers who waved their arms to an inmate band’s Christian worship music.

"God is merciful," intoned Walters, an assistant pastor at one of many churches scattered through this maximum-security prison, informally known as Angola. "God gives us so many benefits."

Walters is a graduate of one of the most unusual prison programs in the country: a Southern Baptist Bible college inside this sprawling facility, offering bachelor’s degrees in a rigorous four-year course that includes study of Greek and Hebrew as well as techniques for "sidewalk ministry" that inmates can practice in their dorms and meal lines.

There are 241 graduates so far, nearly all lifers who live and work among their peers. Dozens of graduates have even moved as missionaries to counsel or preach in other state prisons.

But Burl Cain, the warden since 1995, says the impact has gone well beyond spreading religion among the inmates. He calls the Bible college central to the transformation of Angola from one of the most fearsome prisons in the country to one of the more mellow, at least for those deemed to be cooperative. Watching men quietly saunter from open dormitories to church, many with Bible in hand and dressed in T-shirts of their choice, it can hardly seem like a maximum-security facility, although multiple daily lineups for inmate counts are a firm reminder.

Cain has used religion and peer counseling – backed by sharp discipline for defiant behavior – to promote what he calls a "moral rehabilitation" of individuals and a sense of community among men who might easily be consumed by rage or despair.

"The greatest enemy here is lack of hope," Cain said in an interview.

Cain has lobbied the state for more forgiving parole policies, with limited success. "But if you believe in a higher being," he said, "you’ll realize that when you do pass, you’ll be free."

Nearly four-fifths of the 6,300 inmates now at Angola have sentences of life or so long that they are effectively so. The prison has had to develop its own nursing home and hospice.

Angola was notoriously brutal and bloody into the 1970s. Court supervision and a parade of reforming wardens improved staff training and introduced vocational and GED programs, and the stabbing rate began to plummet.

In Cain’s view, the biggest change came in 1995 when, as he took over the prison and faced drastic cuts in school funds, he invited the New Orleans Baptist Theological Seminary to open a seminary. To his surprise, he said, the eminent seminary agreed, covering the costs with outside donations.

"The Bible college was the game changer," said Cain, 71. "It changed the culture of the prison."

Some other experts say the college is one of many factors, but the softening effect of religion on life here is evident.

Beyond the bachelor’s degrees, the college has granted hundreds more certificates or associate degrees, producing a cadre of men who lead churches, provide informal counseling in their dorms and take on what many describe as their hardest task – informing fellow inmates when a loved one on the outside has died.

The graduates include 15 Muslims, who took the same Bible-based courses but minister to the 250 Islamic inmates.

Some 2,500 inmates attend church regularly, according to Cathy Fontenot, assistant warden – mostly Protestant or Roman Catholic but also Muslim, Jewish and Mormon services. The prison population is 75 percent black, with a small number of Latinos.

The prison college has received growing outside attention. A similar collaboration with a Southern Baptist seminary has started in Texas, where inmates with sentences of at least 10 years are eligible. In-prison Bible colleges have also been started or are under discussion in California, Georgia, Illinois, Mississippi and other states.

For his day job, Walters, a natural-born preacher, tutors seminary students in Greek and Hebrew for their biblical explication. He bunks among the short-timers who are now brought to Angola, improbably enough, for a re-entry program.

The American Civil Liberties Union has watched for signs that the seminary or the prison has crossed constitutional lines by using state money or coercion to promote religion. In the past, the group has sued Angola to force the removal of a biblical citation at the entrance and to give a Muslim graduate of the seminary access to materials from the Nation of Islam, the American Muslim group that is more entrenched in northern prisons.

Still, the seminary appears to be legal because it is paid for privately, is voluntary and admits non-Christians, said Marjorie R. Esman, the executive director of the ACLU in Louisiana.

"I think that what Burl Cain calls moral rehabilitation is, in his mind, religious doctrine, but a lot of good has come of it," Esman said. "I think it’s unfortunate that the only college available is a Christian one, but the fact that a college is there at all is important."

Whether religion, per se, helps create peaceful prisons and reduce recidivism is a matter of scholarly dispute. Byron R. Johnson, a criminologist at Baylor University and the author of "More God, Less Crime," argues that studies have shown the benefits of faith in rehabilitating criminals. He is now leading a long-term study of the impact of the Baptist seminaries inside Angola and the Darrington prison in Texas.

But Winnifred F. Sullivan, a professor of religious studies and law at Indiana University, said, "There is no firm evidence that it is the faith component that makes these programs work."

"Prisons like religion because it keeps people occupied," she said, and "when anyone offers money for programming, it’s attractive."

To gain acceptance to the seminary, men must have a high school degree or a GED, which they can pursue in the prison. They also must have exemplary discipline records and must be recommended by a noninmate chaplain as devout and as a promising minister.

The data indicate a large drop in violence at Angola over the last two decades. In 1990, according to prison records, inmates assaulted staff members 280 times and one another 1,107 times. In 2012, there were 55 assaults on staff and 316 among inmates.

But life is much harder for some inmates than others. Some 1,600 live in more traditional cell blocks because they are considered dangerous, are being punished or need protection. Some of them are allowed outside, in individual cages, for only an hour a day. Some work in the farms for pennies per hour, guarded by a horse-mounted armed officer.

This year, four members of Congress asked the Justice Department to investigate what they called the illegal use of solitary confinement by Angola and other state prisons, citing the cases of two prisoners, self-described Black Panthers who spent the last four decades in near isolation after being convicted of murdering a prison guard. One of the men, Herman Wallace, was released last week after his 1974 murder conviction was overturned, only to die on Friday of cancer.

Walters, the seminary graduate and pastor, admitted that some inmates detested him for his religious devotion and implicit cooperation with the authorities. But he said, "If I can help other people while I’m marching to the grave here, then I’ll have lived a good life."

© 2013 The New York Times Company