usic written centuries ago to herald the monthlong Advent season will resound off the vaulted ceiling of the Cathedral of St. Andrew on Sunday.

“This Sunday is a big, big deal,” said the church’s music director, John Robert Renke. “People say it just changes their whole preparation for Christmas. It’s very reverent, calming and meditative; it brings the hype down. It reminds us of why we have the holiday. Even people who aren’t churchgoers come. All the candles are lit throughout the cathedral; it’s a beautiful atmosphere.”

“The Advent Procession With Carols,” one of several programs that pack the pews every year during the holidays, is scheduled for 5:30 p.m., but “it’s not ‘Jingle Bells’ you’ll hear,” Renke said.

“This is counterculture to all (that),” he added, referring to holiday tunes playing in stores and malls during after-Thanksgiving sales.

Celebrated over the four Sundays preceding Christmas, Advent is the “slightly penitential, reflective” period that prepares the faithful for the birth of Jesus Christ, said Renke, who also serves as the main organist and director of the Cathedral Choir, whose repertoire comprises highly complex, classical cathedral music, mostly sung in French, German and Latin.

It’s only at the “Festival of Lessons &Carols,” slated for 5:30 p.m. Dec. 25, that everyone can sing the old caroling favorites.

“When you hear ‘Hark the Herald Angels Sing’ and you have this roaring acoustic” of the music bouncing off the limestone pillars and ceiling vaults, “there’s nothing more powerful. I get choked up playing the organ because it is just so moving,” Renke said.

Renke, who was hired by St. Andrew’s in 2007 to draw the Episcopalian church more deeply into its Anglican (English) musical roots, which extend into the Middle Ages, added, “It’s deeply spiritual music that takes you to a different place.”

The church’s unique music attracts those who are “yearning for something with guts to it (and) that evokes great emotion,” he said. The feedback he gets from parishioners ranges from “that was so prayerful” to “music can take you places much deeper than any words can.”

“The myth is that you gotta have a happy, clappy praise band,” said Renke, who was 15 years old when he first conducted music at a service almost 50 years ago. Even so, he said he tries to offer a full spectrum of music, including contemporary songs.

Ancient sacred music is not for entertainment; it is “pure praise” offered to God. That’s why the Cathedral Choir’s 16 members don’t face the congregation, they face each other in opposite rows. The members, whose ages range from the 20s to the 60s, are highly committed, practicing an hour before each service or concert in addition to a weekly evening session.

At Tuesday’s a cappella practice, choir members kept the beat with their entire bodies, swaying, bobbing their heads and tapping their toes as they sang, even though Renke was conducting. Some had pencils tucked behind their ears to jot notes on their music sheets.

Karen Sender, who has sung soprano in the choir since 2002, said, “We’re all reading each other and conducting each other. One of the most amazing things is that chemistry between each of us. As a group, it is the epitome of what I consider ‘being choir,’ knowing we are all part of a whole. We can’t have any prima donnas.

“Music to me is my chief form of prayer,” she continued. “Through singing I can get through anything, no matter how stressful.”

She marveled at the way the building was designed to accent or magnify the sound of voices or the magnificent Aeolian-Skinner pipe organ in its own distinct way. Keep in mind that “they didn’t have electricity in the Middle Ages” when the church’s music traditions began, she added.

Also, the cathedral adds its own magic to Sunday evensong services during winter months, when the sun sets around 5:30 p.m. Sunlight shines through the building’s stained-glass wall, called the “Great West Window,” Sender said, “and all the colors of the window reflect off the stone columns and the floor. It’s just breathtaking.”

For a complete list of holiday services, visit thecathedralofst andrew.org.