Fifteen years after the Rev. Barbara D. Vaughan first heard her calling, seven years after she founded the Holy Light Baptist Church in a rundown theater in Fairfax City, and one year to the day after she rolled up her sleeves and started building near Manassas, Vaughan's voice boomed triumphantly yesterday from behind a brand new pulpit.

"Praise the Lord. The Lord is in His house!" said Vaughan as a gospel choir sang "Jesus, the Light of the World." Instantly, the church swelled with the sound of "Amens."

Many of the congregation had tears in their eyes. As the singing resumed, everyone started clapping and some people began to dance in the aisles. This was a plural victory.

Vaughan and her flock were celebrating the completion of their new church on Old Compton Road near Manassas. Until yesterday, they had met in a community center in the Merrifield area of Fairfax County. Before that, said Vaughan, it was in an old theater.

A year ago yesterday, construction began on a building the church could call its own. Yesterday, piles of mud were on the front lawn of the church, but only a few finishing touches remained to be completed inside.

"It looks good to me," said Vaughan.

"It was my determination that we would give God a new church by 1985," she said. "We did it, one year after we started."

The new building, costing more than $100,000, was paid for entirely through donations, and much of the labor was supplied by the congregation's 100 families.

"We would get off our jobs at 6 or 7, and stay here working until midnight or 1," said Gerret S. Smith, a trustee of the all-black church. " . . . This is a great day in the history of the Holy Light Church."

The day was greatest of all for Vaughan. Identifying herself as the only female Baptist pastor in Northern Virginia, she described her start 15 years ago as a reluctant one.

"The Lord came to me and said I should be a minister. I said, 'I've got five brothers. You must be looking for one of them,' " Vaughan said. "My reaction was I didn't want to do it."

But she did do it, and eight years after becoming ordained, she decided it was time to become pastor of a church of her own. Vaughan said she took what she could get for a location to hold services, but from the beginning, she had a goal: "One thing I didn't want is a building that didn't look like a church . . . . We had to have a building of our own."

However, even now that Holy Light looks like other churches, church members yesterday insisted that it is still different from most. What makes it so -- aside from the woman pastor -- is the rousing, upbeat, brand of fundamentalism practiced at Holy Light, Vaughan said, where even the most lost souls are welcome to join and be saved.

"We are interested in saving people from the devil. We have all kinds of people here . . . . We don't care about where they come from," said Vaughan.

One beneficiary of the open-door policy at Holy Light was trustee Smith. Before he was saved on July 10, 1985, he said, "I used to run the streets . . . . I was into a lot of drugs. I had been to jail. I knew all about 14th Street."

Under any ministry other than Vaughan's, Smith said, "I don't know if I could have been saved."

Nonetheless, like many others in the Baptist Church, Smith said it took him time to become accustomed to the idea of a woman pastor. "I had to overcome [the attitude], you know, that a woman should not be the head. I realized that it is really not Rev. Vaughan that is the head, Jesus Christ is the head of the church."