The new altar is made of pale golden marble, quarried from the treeless mountains of Syria where the Apostle Paul is said to have walked 2,000 years ago.

Paul was converted on the road to Damascus, according to the Bible, and he preached in the ancient city of Antioch, where Jesus's followers were first called Christians.

"We're descendants of that church," said the Rev. George Rados, pastor of Sts. Peter and Paul Antiochian Orthodox Christian Church in Potomac.

Rados stood this week in the sanctuary of his Byzantine-style church on River Road, amid marble dust and the sounds of master stone artisan Soleman Shalhoub and his team at work. The craftsmen were finishing the installation of the new domed altar and arching stone iconostas, an elaborate partition that holds the baptismal font and brilliant painted icons, images of Christ and the saints.

Shalhoub, a Syrian and Orthodox Christian who learned reverence for the ancient stone and for Bible stories from his father and grandfather, stepped back and surveyed the work with pride.

"My heart, my mind, my emotions are all entrenched in my work," he said in Arabic, through an interpreter. To create such an altar and an iconostas "is my passion."

The work has taken four years. Shalhoub oversaw the quarrying and the cutting of the stone. Then, working with 20 classically trained carvers, he saw to it that they hand-fashioned the hard stone into an altar of delicate grapevines and elegant crosses dictated -- in a strangely modern twist -- by e-mails filled with Rados's inspirations and designs.

The tons of individual pieces of carved marble were shipped in 90 wooden crates from the Syrian port of Latakiato Baltimore, then painstakingly assembled over the past month at the Potomac church.

The altar and iconostas are central to the new church, which will be home to a congregation of 350 families that for years have wandered from place to place, said Ruth Ann Skaff, director of development. The parish has worshipped in firehouses, cafeterias and schools.

"It has been a 25-year journey of faith, commitment, dedication," she said.

Since the original formation of the parish of Sts. Peter and Paul, the congregation has grown from 60 members to 1,000. Members bought the land on River Road in 1995 and dedicated the new $4.5 million church complex in 2001; a formal consecration ceremony is scheduled for Oct. 9.

Nationally, the ancient denomination has grown, as well. The Antiochian Christian Archdiocese of North America now claims nearly a half-million members.

Some members are converts from evangelical traditions, attracted by both the denomination's conservatism on social issues and celebration of ancient mysteries through singing, chanting and anointing.

At Sts. Peter and Paul, work on the new church continues.

"It's an ongoing vision," parishioner Steve Simon said.

Where now are blank walls, Rados sees more beauty to come. Next, the church's central dome will be embellished.

"My interest," said Rados, "is to create an atmosphere of heaven."

This is not frivolity, as Rados sees it, but rather the creation of a sacred space that inspires godly lives.

"This will be decorated with all the saints," he said, "to uplift us and help us be good Christians."

The Antiochian Orthodox have many rituals that involve the architecture of their church.

On Easter, they stand outside the building and pound on the door.

They ask the question, "Who is the King of Kings?"

Finally they are let in.

"You ask the question outside," Rados said. "Inside is the answer."

So the church building itself becomes a living symbol of the ancient life of Christianity, he said.

"Our church is coming back to the ancient architecture because of the beauty and hard work . . . the authenticity. It's the rebirth of the ancient church here in America."

Tomorrow, before Shalhoub returns to Syria, Rados will say his first Mass on the new altar.

"I'll be awed," he said. "I'm not worthy to be at such a beautiful altar."

Syrian artisan Bassam Albarshini touches up the marble arch at Sts. Peter and Paul Antiochian Orthodox Christian Church. The arch and altar have taken four years to finish.Soleman Shalhoub, above left, with the Rev. George Rados, came with his team of artisans to Potomac from Syria to create a large, marble arch and altar for Sts. Peter and Paul Antiochian Orthodox Christian Church. To create such an altar and an iconostas "is my passion," he said. Murals, such as this panel of Saint Peter and Saint Paul holding a replica of the Sts. Peter and Paul Antiochian Orthodox Christian Church, remind church-goers of their denomination's ancient beginnings. "My interest," said the church's pastor, the Rev. George Rados, "is to create an atmosphere of heaven."