It’s Saturday morning at San Quentin, and the prisoners are trickling in for services at Congregation Beth Shalom.

Many of the men have fading tattoos that protrude out of their collars or rolled-up sleeves. They walk in single file, picking up yarmulkes from a basket near the door. Each grabs a prayerbook, takes a seat and places his clear plastic bag of belongings under the chair.

There’s a decent turnout this week — a multiracial, mixed-age group of about two dozen dressed in uniforms of jeans, denim shirts and running shoes, with the word “Prisoner” clearly visible on every article of clothing.

Carole Hyman, the prison’s Jewish chaplain and the congregation’s spiritual leader since 2004, is a petite, middle-age woman with salt and pepper hair. Dressed in a casual pair of slacks with a button-up shirt, she stands near the door wearing a kippah and prayer shawl and personally greets each man by first name.

Before getting started, she moves a compact Torah sitting on a card table to the front of the makeshift shul, a small room with dingy walls and flickering fluorescent lighting. A rug sits in the middle of the floor and the words “Al-Islamic Space” are posted on a placard; the space is shared with the prison’s Muslim community.

“It’s another San Quentin Shabbat!” she announces at precisely 10:30 a.m.

Seated in a semicircle under the watchful eyes of guards, the men recite the blessing for putting on a tallit as they kiss the corners of their prayer shawls and drape them around their shoulders.

The service continues with prayers in English and Hebrew, singing and responsive readings, ending an hour later when Hyman leads the Kiddush over grape juice and fresh challah from Whole Foods.

Congregation Beth Shalom, or “House of Peace,” serves California’s largest incarcerated Jewish population in what is considered one of the state’s safest correctional facilities, due to its makeup: The majority of inmates are serving life sentences with the possibility for parole, have done a lot of time and are middle-age. “They are trying to be good citizens while they are here, and they are trying to go home,” Hyman says. Also, “there are more possibilities to rehabilitate” through certificate programs and self-help workshops.

“It’s a stable and safe place [for Jews] compared to other prisons,” adds Hyman, who has been a Jewish prison chaplain for more than 15 years at correctional facilities in California, including the state prison in Vacaville. “Other correctional facilities in the state have more white supremacy activity. At those institutions, there would be more reason for people not to admit the fact they are Jewish. Harassment can [easily] lead to physical violence.”

Of the more than 4,000 prisoners at San Quentin, Hyman estimates that 80 inmates identify themselves as Jewish; 45 are in the mainline population, and another 35 are on death row and cannot attend mainline services, although Hyman works with them three days a week.

Overlooking the San Francisco Bay among the area’s wealthiest ZIP codes, the prison in unincorporated Marin County is the state’s oldest. It looks more like a fortress than a correctional institution.

Built in 1852, San Quentin State Prison houses California’s only death row inmates. Executions took place onsite until 2006, when U.S. District Judge Jeremy Fogel ruled that lethal injection constituted “cruel and unusual punishment.” That resulted in a moratorium on capital punishment in California that stands today, leaving condemned prisoners in limbo.

The men serving time here are some of California’s most hardened criminals, convicted of rape, kidnapping and other violent crimes. The majority are serving 25 years to life.

Beth Shalom member Richard Benjamin, 52, has been in prison for two decades, convicted of robbery and kidnapping. Like many inmates, he says he is not guilty.

Benjamin was not raised Jewish. In fact, he grew up Southern Baptist and became interested in Judaism after discovering that his mother’s birth certificate identified her as “Negro and Jewish.”

“Judaism just fit,” says Benjamin, who participates in all of the Jewish activities offered at San Quentin. “I felt like I just belong here.”

Benjamin started the conversion process at Folsom State Prison in 2009 with Rabbi Ira Book, chaplain at the Sacramento-area facility. “We couldn’t do everything, but I was able to have a bar mitzvah,” he says.

Completing a conversion while behind bars is nearly impossible for a variety of reasons, Hyman says. According to halachah, or Jewish law, a person cannot convert when he or she is not free. There are also logistical problems, including the absence of a mikvah on prison grounds (a new convert must immerse in the ritual bath).

For prisoners raised in a Jewish household, Hyman says, the weekly services and midweek Torah studies she offers provide “a joyous reconnection to Judaism” and often trigger memories from their Jewish childhood.

In the population she serves, Hyman says few come from a household with Jewish parents. About half of the inmates who show up on Saturday mornings are African Americans who were already incarcerated when they decided they wanted to convert to Judaism.

Many of the inmates who identify with Judaism, or who are working toward conversion, say they became interested after tracing their family roots and finding something — or someone — who was Jewish.

Rabbi Menachem Katz, director of prison and military outreach at the Aleph Institute, a Chabad-affiliated nonprofit based in Florida that advocates on behalf of incarcerated Jews, says there are reasons a prisoner might seek to convert to Judaism that are unrelated to presumed Jewish lineage.

“Life in prison gets monotonous and religion is something to do,” Katz says, adding that some inmates are motivated by the kosher diet plan. Aleph works with prison administrations to make sure kosher meals are available, along with sanctuary space for worship. At San Quentin, 55 inmates are on the kosher meal plan after approval by Hyman, who reviews the applications.

Rabbi Yossi Stern, Aleph’s director of religious education, estimates there are about 300 Jewish prisoners in California and 1,400 federal Jewish inmates in the country’s prison system. One of the problems Jewish prisoners face while incarcerated, he says, is that First Amendment rights that protect freedom of religion do not extend to the finer points of Jewish law.

“Jewish inmates face several issues,” Stern says, “from not being allowed to have tefillin to having issues with the kosher meals being mixed with mainline food.” He says much of Aleph’s prison outreach work is making sure there are items such as grape juice on Shabbat, matzah on Passover and an etrog on Sukkot.

“Every inmate and prison has a different issue,” Stern says.

Prison spiritual work is a second career for the 66-year-old Hyman, who discovered it after a long career in the wine industry. She was working as a consultant for a vineyard in Hungary in the late ’90s when she decided to track down the village of her paternal grandparents, just over the border in Slovakia.

“I got so excited and figured I would visit,” she says, “but when I arrived at my grandparents’ village, I saw the devastation of the Jewish community, and it had a tremendous effect on me.”

After returning to the U.S. from Hungary, Hyman — who “had a strong Jewish identity, but lacked a Jewish education” after growing up Reform in Washington, D.C. — searched for ways to reconnect. Her search led her to Berkeley’s Graduate Theological Union and the Pacific School of Religion, where she received a master’s in divinity in 2000. She received a doctorate in pastoral care and counseling from the San Francisco Theological Seminary. During her education as a chaplain, she worked in hospice, hospitals and correctional institutions.

“[At first] I had the assumption that there can’t be many Jews in prison, or if there were, they were in for white-collar crimes,” Hyman recalls. “I was also very interested in marginalized populations and people who were not necessarily Jewish, but interested in learning about Judaism.”

Hyman believes her work in the Jewish community at San Quentin has value because it addresses spiritual and ethical needs specific to inmates.

Outside in the “yard,” the space where most inmates spend their days working out, San Quentin public information officer Sam Robinson points out how the men divide themselves by race and ethnicity, each keeping to his own kind. “The blacks are in the basketball court, and the Pacific Islanders are at the [pull-up] bars,” he notes. But religious activity “is one of the only places where you will see different races mixing. Otherwise, protection lies within groups of people who look like you.”

Hyman gets high praise from her congregants on the work she does bringing the Jewish community together. “Discrimination is very strong in prison,” says Beth Shalom regular Carl Samson, 68, from Los Angeles. “There are racial, religious and gang issues, but we try to put that all aside when we are in here.”

Inmate Andrew Halperin, 57, says he asked to be moved from another California facility to San Quentin last year because of its Jewish community.

Halperin was brought up in a Jewish household in Los Angeles, had a bar mitzvah and was confirmed. He’s been locked up for nearly three decades. But it wasn’t until he was transferred to San Quentin that he was able to comfortably resume his Jewish identity.

“I didn’t hide it, but it wasn’t something I volunteered, either,” he says. In other facilities, Halperin says he was housed with skinhead “cellies” and was forced to figure out a way to make peace with them.

“I’m not a religious person at heart, but I believe in God. I believe in treating your neighbor well,” he says. “In prison, you have a lot of time to think, and the Jewish community offers you an exercise in camaraderie.”

That’s something Joey Mason, 53, has learned as well. He is serving a 25-to-life sentence,  with another 10 years before his case comes up for parole. Mason found Judaism after being locked up. “I’ve done enough in my life to give myself guilt and shame,” the Georgia native says. “Being Jewish helps me stay grounded and mindful. God and I are in line. I do a lot of mitzvahs and give back to my community.”