When the Rev. Roberta Finkelstein became the first full-time minister of the Unitarian Universalists of Sterling in 1997, about 45 worshipers were meeting at the Sterling Annex Community Center. Each week the congregation held services on folding chairs on a squeaky gym floor, unpacking and repacking a chalice, candles, hymnals and other supplies. Office space was a rented room above a used bookstore nearby, and weekday meetings or religious classes were squeezed in at members' homes.

Finkelstein was hired for a five-year term -- it was extended by the church indefinitely -- to help establish a congregation that had been formed slightly more than a year earlier. Now more than 90 people attend Sunday worship at Sterling Oaks Commerce Center, where the church has room for a suite of offices and Sunday programs for children.

For Finkelstein, 52, her original mandate has been fulfilled, and it's time to move on. Today is her last day.

"I must leave the future of the church in your hands," Finkelstein told the congregation at her farewell sermon June 5. "It has never been my church or my ministry. It was and is your church and your ministry."

Under Finkelstein's stewardship, the church has become known in Loudoun County as a vocal center for social activism. It collects nonperishable food weekly for Loudoun Interfaith Relief and has participated in a series of interfaith forums with local Muslims and people of other religions in the wake of the terrorist attacks of Sept. 11, 2001. The church is recognized by the Unitarian Universalist denomination as a "welcoming congregation" for bisexual, gay and transgender people and has conducted letter-writing campaigns and circulated petitions supporting same-sex marriage and benefits for homosexual couples.

Steve Dick of Ashburn, a founding member of the church, said it has been imperative for the congregation to be involved with social issues as well as spiritual ones.

"A church like this plays a role in the larger society as the voice of a liberal religious community," said Dick, 55, who works for NASA.

And "Rev. Roberta," as she is known by the congregation, has been a central force in leading the Sterling congregation to this point.

"Churches have development stages the way people do and companies do," Finkelstein said in an interview. "I'm feeling the church needs a different kind of person."

Finkelstein will spend at least a year as an interim minister at the Unitarian Universalist Congregation of Frederick, helping the group find a permanent leader while she seeks a congregation of her own. She said she is looking for a church where she can continue to pursue her activism, perhaps in the Northeast or on the West Coast. Ideally, she said, it would be near the ocean, her "spiritually calming place."

The ministry is Finkelstein's second career. She spent a decade as a nurse, including several years as a midwife. She was a lay leader at the Unitarian Universalists of Arlington, when one Sunday she was asked to give a sermon while the minister was on vacation.

"I stepped into the pulpit, and I loved it," Finkelstein said. She enrolled in seminary at age 36, the same year her son, now 22, started kindergarten. During her studies, she interned at churches in Shenandoah and Manassas.

"The ministry is so perfect for her," said her husband of 30 years, Barry Finkelstein, a member of the church's choir and jazz band. Although his wife's calling came as a bit of a surprise at first, once he saw her in action, "it just seemed so right," he said.

Unitarian Universalism -- or "UUism" as members sometimes call it -- is a pluralist faith incorporating teachings of Judaism, Christianity and other world religions. It was formed in 1962 as a merger between the Unitarians, a Reformation-era tradition emphasizing belief in one God, rather than in a trinity, and the Universalists, who believe in salvation for all and reject the concept of hell.

Adherents, who have no official creed, say it is possible to have faith without believing that other religions are wrong. They emphasize reason, broad-mindedness and experience as sources of wisdom. Some congregations avoid using the word "church" in their names because of its Christian implications, although Finkelstein uses the term to mean a group that shares the same faith.

That's an idea emphasized by the church's adult education program, "Bible for Liberals," which studies the text with what Finkelstein calls "a very open-minded and scholarly perspective" without necessarily accepting the Bible as literal truth. Instead, the group examines the original historical context of a passage and what scholars have said about its modern relevance.

"Everyone has their own understanding of the truth," said Finkelstein, who in her services has drawn from the Bible, texts from other religions, philosophy and poetry. She once gave a sermon titled "The Theology of the Beatles," using the band's lyrics to explore themes of human experience. "No one can get it completely right or know for sure," she said.

Finkelstein was born in Brooklyn, N.Y., and raised in Queens and on Long Island. Her Jewish father and Episcopalian mother raised her in the Unitarian church. Both at home and at church, she was active in the civil rights movement.

"I marched in the streets for equal rights and for peace and for justice," Finkelstein said. "I simply followed my minister and my mother out the door."

Her activism continued in college, where she met her future husband and joined with him in protests against the Vietnam War. Over the years, Finkelstein has served on the board of Loudoun Volunteer Caregivers and was a founder of what is now the NARAL Pro-Choice Virginia affiliate.

In addition to pursuing her own activism, Finkelstein has tried to create a congregation in which members take initiative in starting and furthering community projects.

"She's prepared us well to continue the journey," said Dave Scher, 38, a legal technology consultant nearing the end of his year-long term as congregation president.

Scher said he joined the UU of Sterling in the summer of 2000 with the expectation that it would provide an environment in which his children could learn about different faiths, but the church had an impact upon him as well, especially as he became active with FoodSource, which provides meals to the needy in Fairfax County in partnership with the All Dulles Area Muslim Society.

"The more I participated, the more spiritual I got," Scher said. "[Finkelstein] knows, as do we, how imperative that kind of action is in our faith."

The congregation will say its final goodbyes to Finkelstein today, although the details are secret to the departing minister. Once she leaves, that's it. Finkelstein said she considers it her ethical responsibility to "be gone" after her resignation takes effect. No more lunches with congregation members or visits to their homes.

"Whenever I'm with people from the congregation I'm at work," she said. "When the ministry ends, the relationship ends."

In August, an interim minister will join the congregation as it searches -- at least for a year, maybe two -- for Finkelstein's successor. And then begins the next stage of growth: Church members hope to save enough money to buy a permanent home.

Finkelstein greets Monika Thiel and her 2-year-old son, Nicholas, with usher Shelley Tamres. The Rev. Roberta Finkelstein gave her last sermon in Sterling on June 5.