The oldest church in the District sits in historic Rock Creek Cemetery, but many Washingtonians don't seem to know it's there. With this week's completion of $9.5 million in renovations to its sanctuary and parish hall, the dwindling congregation of 150 or so hopes that situation will change.

The hope, members and leaders say, is to bring new life to St. Paul's Episcopal Church, Rock Creek Parish, a congregation that has survived nearly 300 years but whose future is uncertain because of a rapidly aging constituency with too few children to support a Sunday school program.

What the church does have are assets that would be the envy of most congregations: 86 pastoral acres in the nation's capital, an 18th-century chapel with acoustics that music director Graham Elliott calls "a musician's dream," one of the largest parish halls in the area and an investment portfolio of $40 million.

Yes, that's a lot of money for a small congregation, said senior warden Blair Ewing, who chairs the church's nine-member vestry board. And the dividends from that endowment cover a large portion of St. Paul's $2 million annual budget -- much of which goes for upkeep on the churchyard, a public cemetery filled with generations of politicians, bankers, entrepreneurs, librarians, judges, generals, diplomats, scientists and writers.

But the portfolio is "a mixed blessing," especially when it comes to the capital campaign to upgrade and expand the 1928 parish hall and restore the 1775 chapel, said Ewing, 70, whose ancestor Caleb Litton was one of the church's founders.

Many in the congregation, whose average age is probably 40 to 50 (no one knows for sure), don't understand why they have to raise millions of dollars for the renovations when there's money sitting in the bank.

The answer, Ewing said, is that raiding the portfolio, created from long-ago sales of timber and a variety of more recent real estate transactions, could undercut the church's financial future -- especially when the money is invested in a stock market that has had some down years recently. A line of credit has been established, but the church's future could lie in its ability to attract new members.

And that depends on the church defining, or redefining, its mission, said Ernest Garner, 70, a member since 1965 and chairman of the investment committee. "Buildings and facilities are tools," said Garner, a semi-retired physicist. "If you want to grow, you have to have a spiritual base of some magnitude."

About four years ago, around the time St. Paul's decided to go forward with the renovations, it made another decision that took the church in a dramatic new direction. It hired Elliott, a well-known organist in England, to take over the music program and create a center for sacred and classical music in the heart of Rock Creek Cemetery.

Elliott, a native of Wales, was organist for 18 years at Chelmsford Cathedral (30 miles northeast of London), where he established an international music festival that ranks among the finest in England. He also raised millions of dollars for a music scholarship program and to build two new organs at the cathedral.

St. Paul's had advertised for a new music director, and Elliott said he was intrigued with the prospect of coming to a historic U.S. church with a more extensive property than most cathedrals -- including Washington National Cathedral, where he directed the choirs at a memorial service for terrorist attack victims three days after Sept. 11, 2001.

Elliott, 55, has been a driving force behind renovations at St. Paul's, bringing in liturgical and acoustical consultants to help make the small theater in the parish hall a proper venue for musical performances and reconfigure the chapel to accommodate a custom-made $500,000 Dobson pipe organ.

In 2001, he organized the first Rock Creek Festival, a weeklong arts event hosted by the church on its grounds. The second festival begins tomorrow with an evensong performance by Elliott on the new organ and continues through Saturday, with daily concerts featuring a variety of music: Caribbean, big band, chamber music, jazz, sacred and classical.

Other activities include a walking tour and photographic exhibit of the cemetery, which is filled with mausoleums and sculptures, including the famous Adams Memorial by Augustus Saint-Gaudens -- commissioned in 1885 by Henry Adams for his wife, Clover, who committed suicide at 42.

The festival, intended to be an annual event, is just the beginning of what Elliott hopes is a major means of invigorating the church and bringing it new recognition -- and members.

"I strongly believe our mission is to let people know that Rock Creek is not just a cemetery but the churchyard of the oldest church in Washington," he said. "My dream some years hence is to have enough [backing] to host a huge outdoor gala concert with an outdoor stage."

Whether an annual festival and St. Paul's enhanced music program will attract enough members to bring new life to the parish remains to be seen. But outsider Mary Ann Ruehling, 53, a Defense Department employee, was persuaded to join after hearing Elliott play Sunday evensong two years ago -- before restoration began.

"It was a lovely service in a lovely church, quite an atmosphere of worship," said Ruehling, who added that she wondered whether it would feel strange "tramping about the roads in the cemetery" on the way to the church.

Instead, she found the experience to be "very beautiful" and very spiritual. "I think of all the souls and prayers that have passed there through the centuries. It's an honor to those [who worshiped in the past] while taking the church forward."

Garner, who admits apprehension about committing so much money to renovations at once rather than incrementally, said he nonetheless has great hopes for the music program envisioned by Elliott.

"Graham brought a different view, a strong sense of innovation, creativity and the tradition of the Anglican Episcopal Church," said Garner, who was raised Baptist but confirmed as an Episcopalian 49 years ago. Although St. Paul's didn't realize it at the time, Elliott turned out to be "a customized fit," he said.

Ewing, too, acknowledged moments of anxiety about spending millions to improve buildings before expanding membership.

"It's a different approach to building a church," he said. "Most build congregations, then buildings. We're doing the opposite. We're all hoping it works."

The second Rock Creek Festival begins at 4 p.m. tomorrow with a free evensong service and continues through Saturday at St. Paul's Episcopal Church, Rock Creek Church Road and Webster Street NW. Daily 7:30 p.m. concerts are $20, $10 for senior citizens and students. Lunchtime performances and other events are free. Call 202-726-2080 or go to the church's Web site at www.rockcreekparish.org.