Some say the UUA is held back by members’ reluctance to proclaim religious tenets—a tricky task for an association that includes Christians, Buddhists, Jews, pagans, humanists and spiritual refugees from a host of more dogmatic faiths.

A recent Sunday service at the First Unitarian Church of Baltimore ended with an apology.

Laurel Mendes explained that religious doctrine had been duly scrubbed from the hymns in the congregation’s Sunday program.

But Mendes, a neo-pagan lay member who led the service, feared that a reference to God in “Once to Every Soul and Nation” might still upset the humanists in the pews.

“I didn’t want to make anyone uncomfortable by reciting something that might be considered a profession of faith,” said Mendes, 52, after the service. “We did say `God,’ which you don’t often hear in our most politically correct hymns.”

Welcome to a typical Sunday in the anything-but-typical Unitarian Universalist Association, a liberal religious movement with a proud history of welcoming all seekers of truth—as long as it’s spelled with a lowercase “t.”

Dramatic readings from the biography of 20th-century labor leader John L. Lewis? Sure. An altar crowded with Christian, Buddhist, Islamic and Jewish symbols? Absolutely. God-talk? Umm, well …

For 50 years the UUA has conducted a virtually unprecedented experiment: advancing a religion without doctrine, hoping that welcoming communities and shared political causes, not creeds, will draw people to their pews.

Leaders say its no-religious-questions-asked style positions the UUA to capitalize on liberalizing trends in American religion.

But as the UUA turns 50 this year, some members argue that a “midlife” identity crisis is hampering outreach and hindering growth. In trying to be all things to everyone, they say, the association risks becoming nothing to anybody.

The UUA does promote seven largely secular principles that emphasize human dignity and justice.

Membership in the UUA dipped in 2011 for the third consecutive year, to 162,800, a loss of about 1,400 members. The number of congregations fell by two, to 1,046.

The UUA was formed in 1961 by the merger of two small, historic groups: Unitarians, who believe in one God, rather than Christianity’s traditional Trinity; and Universalists, who hold that God’s salvation extends to all, regardless of race, creed or religion.

Nearly 4,000 Unitarian Universalists gathered in Charlotte, N.C., last week (June 22-26) for the association’s annual assembly, where they celebrated their golden anniversary with hymns, remembrances and a large cake.

As usual, progressive politics prevailed, with pledges for an “institutional commitment” to ethical eating, an anti-discrimination rally and a special collection taken for ministry to immigrants.

Such activism dates to 19th-century Unitarian godfather William Ellery Channing, who argued that the aim of religious life is to encourage public virtue.

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