Fifty-four cast members stood or knelt at the front of the First Parish Unitarian Universalist Church on Sunday for the Pageant of the Nativity, a performance the historic downtown Portland church has staged for 90 years in a row.

Mary cradled the baby Jesus. Joseph gazed into their faces. The angel Gabriel and his attendants looked on while the Magi and a flock of apostles moved in. Suddenly the group melded into a living tableau straight out of a 15th-century Fra Angelico fresco while organ music soared in the background.

The pageant is the congregation’s annual Christmas gift to the community. Written by the Rev. Vincent Silliman, minister of the Congress Street church from 1926 to 1938, the pageant has been presented virtually unchanged every Christmas season for nine decades.

Since the pageant began, tens of thousands of people have watched it.

The Rev. Jill Saxby, a guest of the church who narrated the pageant, said “it’s a real Portland tradition.”

“When you’re here, you really feel how steeped in history this is,” Saxby said after the pageant. “It takes you out of the Christmas crazies and it gives you the purpose of the season.”

Saxby narrated the story of Jesus’ birth as Sunday’s performers silently acted out the scenes, accompanied by many religious songs, such as “O Come All Ye Faithful,” “Silent Night” and “O Little Town of Bethlehem.”

Some roles are passed down from generation to generation. This year’s cast featured several third- and fourth-generation members, said Laurie Hasty of Falmouth, the producer who has been involved in the pageant since she was a child and her father was the minister.

“People like to keep it in the family,” said Hasty.

Sharon Merrill of Portland has volunteered at the pageant for the past 34 years, first playing Mary for three years and more recently helping out as assistant director in charge of the apostles, keeping them on cue and in costume.

Asked why she keeps coming back, Merrill said simply, “Oh, tradition.”

The costumes play a major role in the pageant. Some of them are made of shimmering fabrics brought back circa 1924 from what was then Palestine by the nieces of Henry Wadsworth Longfellow. Longfellow’s family belonged to the church, and a plaque notes the pew where they sat.

Some of the turbans were fashioned by the church’s ladies’ auxiliary from their own hats in the 1930s.

Costume mistress Bette Brunswick of Saco, a professional bridal seamstress, oversees the packing, unpacking, ironing and repairing of the delicate costumes, a job she took on a decade or so ago when the previous costume mistress grew too old and frail to continue.

“We really count on the candlelight to obscure the repairs,” said Brunswick.

The church is hoping to obtain a grant to store the costumes on padded hangers in an acid-free environment, Brunswick said.

It wasn’t until recently that any of the pageant directions were written down; the auxiliary ladies depended on their memories to recreate the pageant from year to year. Now, however, everything is in writing because people’s lives are much busier.

Church members say the pageant is intended to celebrate the birth of Jesus by underscoring the meeting of East and West in the presence of the symbolic spirit of good will. They say taking part in the pageant is special.

“It gives me a sense of peace,” said William “Billy” Hobbs of Wells Beach.

Hobbs has performed in the pageant for 51 years and inherited the role of the apostle Peter from his father, who performed with the Nativity play in the 1960s. Hobbs’ four brothers and his sisters-in-law have been involved. This year the next generation, Hobbs’ nephew Tyler Hobbs, stepped in to continue the tradition.