When the Unitarian Church in Westport, Connecticut, asked Victor Lundy to design its first church building, he imagined a pair of hands in prayer. Pressed together they represent submission, but when pulled apart in a pose of questioning, they let the light through. Parishioners arrived at their finished church in 1965 to find it capped by twin roofs that rise on either side of the altar and reach toward the sky in parallel pinnacles that never meet. Sunlight illuminates the sanctuary through a well-placed skylight. The spires, Lundy said, represent the “open question” at the heart of Unitarian Universalism, a denomination that has shed the dogma of its Christian roots in favor of an ecumenical search for meaning without ever espousing a singular truth.

For a small denomination that sits proudly on the left fringe of American religious communities, Unitarian Universalism boasts a surprisingly impressive roster of churches by major modern architects. Though tradition generally looms large in religious building, many Unitarian Universalist congregations have embraced a design approach in line with their progressive temperament. In modern architecture they found an affinity of style and worldview, and subsequently sought out architects like Frank Lloyd Wright, Louis Kahn, Paul Rudolph, and Edward Durell Stone. Looking for designs that are less high altars of worship than spiritual gathering places, the congregations have found that the flexibility of modern design meets their preference for ambiguity over absolutes and humanism over hellfire.

Historically, much of the world’s important and lasting architecture has been religious—from Greek temples to European cathedrals. The awe inspired by their marble masses and soaring vaults was located somewhere between the sheer power of God and the possibilities of man working in his service. Though today’s celebrity architects focus on high-profile museums and concert halls (our places of secular devotion), for millennia creating sacred space was architecture’s principal concern.

In most religious buildings, architectural boundaries have been established by centuries of tradition. Cathedrals from Notre Dame to Westminster may reflect different styles and ornamentation, but their plans are nearly always based on the axis of a cross. Mosques face Mecca and share the common spire of the minaret, and synagogues around the world are pointed toward Jerusalem. But as a denomination, Unitarian Universalism offers architects freedom: It has no creed (not even central agreement on belief in God) and emphasizes diversity and equality in beliefs and backgrounds. Many congregations have found that by breaking from the traditional ecclesiastical blueprint, the very notion of sacred space could be redefined as well.

Unitarian Universalism has its roots in New England Puritanism, though the two sects—Unitarians and Universalists merged in the 1950s and 1960s—quickly rejected established Christian orthodoxies like original sin and the holy trinity. As Unitarian and Universalist congregations expanded throughout the country in the 19th century, they turned their focus away from the hereafter and distinctly toward the present. While holy rollers preached damnation at tent revivals across the land, Unitarians and Universalists tucked into the good work of abolishing slavery and promoting women’s suffrage. When it came time to build, they embraced the styles of the day.

Free from the burden of tradition, Unitarian and Universalist congregations felt no need to mimic ecclesiastical architecture of the past. Gilded Age architect Frank Furness designed a new building for the First Unitarian Church of Philadelphia, where his father had been a legendary abolitionist minister for 50 years, which was completed in 1886. A.C. Schweinfurth designed a rustic turn-of-the-century gabled wooden church in Berkeley, California, and H. H. Richardson’s church in Springfield, Massachusetts, was built in his typical Richardson Romanesque style.

In 1905 the Universalist congregation in Oak Park, Illinois, commissioned local iconoclast Frank Lloyd Wright—a Unitarian himself—to design a new church after theirs burned down. Wright set out to create a structure that, as he put it, would embody “the principles of liberal religion for which this church stands…unity, truth, beauty, simplicity, freedom, and reason.” Rather than steeples reaching for the heavens, Wright created a closed, intimate space whose squat, earthbound configuration invites human connection.

The square room’s nine different seating areas face each other, and with no pew more than 40 feet from the pulpit, Wright engineered an intimacy between clergy and congregation. “This is symbolic of the theology of our tradition, wherein the minister is called out of the congregation as a part of it and not placed in it from the outside,” says retired architect and Unitarian Universalist minister William Haney. Alan Taylor, the congregation’s senior minister calls the church, known as Unity Temple, “a container for worship.” “There’s a sense of the divine or God coming into the space, rather than the space trying to reach up for God,” he says.

In the 1950s and 1960s, as the Unitarians and Universalists merged into their current unified form and many of their parishioners moved to the suburbs, a number of congregations sold their urban properties and followed suit. Architecturally minded and flush with cash, Unitarian Universalism underwent something of a small building boom. Paul Rudolph was commissioned to design a new building for First Church in Boston (a congregation then 338 years old, originally chartered by colonial governor John Winthrop); Pietro Belluschi set to work on a church in Rockford, Illinois; Edward Durell Stone built one in Schenectady, New York; Alexander Girard designed a wood-mosaic mural for a church in Albuquerque, New Mexico; and Louis Kahn designed a church in Rochester, New York.

The original meeting houses of the 17th century had a spare, functional quality that found easy expression in modernism’s stripped-down aesthetics. A battery of new churches built on the congregational intimacy of the faith’s roots were also expressions of high modernism’s desire for simplicity, open interiors, and hostility to gaudy ornamentation. Lundy’s church in Westport—nicknamed the New Ship Church, after the sail-like shape of its swooping roofs—is possessed of just that sense of history and is a canny homage to the 1681 Old Ship Church of Hingham, Massachusetts—the oldest Unitarian Universalist meetinghouse in continuous use.

Another point of convergence was the embrace of the natural world. Modern architects who were eager to use natural materials and play with the relationship between indoors and out had a receptive audience in congregants who found spiritual inspiration in the natural world. “Nature often has an important theological position in many of our churches,” says Haney. “We’ve inherited from Emerson and the Transcendentalists, and exposure to nature through clear glass rather than the mystery of stained glass has become an essential part of our architecture.”

Modern architects also found ways to express the absence of hierarchy in the congregations for which they were building. Belluschi used movable chairs instead of pews for seating, emphasizing flexibility in use and renouncing the dogmatic positioning of the minister at the front preaching truth to those assembled. Kahn’s Rochester church did the same thing. Although much recent American religious architecture seems to have taken the Metrodome as its point of reference, Unitarian Universalist congregations continually look to high design to create their sacred spaces.

In 1993 Edward Larrabee Barnes designed a church in Manhasset, New York, and in 2008 the Wisconsin firm Kubala Washatko completed a LEED Gold–certified addition to Frank Lloyd Wright’s First Unitarian Society Meeting House in Madison. The congregation made as many sustainable choices as they could, while never losing sight of their church as a place for fellowship. The chairs are placed so that people make eye contact with each other. “You can see those who are feeling joy,” says project architect Vince Micha, “and others who are experiencing sorrow, and the design gives the opportunity to talk to them after a service, and support them.”

Sacred space, as ever, is as much about community here on earth as it is in heaven. As this uniquely American sect continues to move with the times—both social and architectural—it proves that when it comes to church, God is in the details. Not that the Unitarian Universalists are insisting that there is one.