John Heizer played the Sunday service at the historic Zion Church of the City of Baltimore for the last time, taking his seat at the pipe organ on the upper level of the sanctuary, a perch he occupied for 50 years.

Pastor Anke Deibler acknowledged the milestone at the start of her sermon and requested applause for Heizer. A city official declared the day for him. But if Heizer expected a profound feeling of finality, he didn’t get one.

A modest Heizer seemed to shrug it all off, saying the day felt more or less like the few thousand Sunday mornings before it. That is how the end arrived for Heizer, leaving the number, 50 years, to speak for itself.

The mezzanine he once shared with a full choir was empty. He was alone except for his successor, a Peabody student named Nathan Ringkamp who was young enough to be his grandson and sat at his side and watched. Heizer was also a student, 58 years ago, at the Peabody institute’s organ program.

The congregation for the early service, held in German, numbered 16; that number doubled for the late morning service, held in English. That made last weekend a well-attended one by comparison to most for a church that holds hundreds and is almost as old as the city itself. Zion was founded in 1755 by German immigrants who arrived in Baltimore. They put their first church within a block of the current one on East Lexington Street. It has stood there in its current form since the 1840s when it was rebuilt after a fire.

The empty pews, empty chairs and unused music stand where singers would otherwise be dimmed the scale of Heizer’s achievement. He has played at the church since July 1974, providing music for generations of congregants.

Heizer said “it was time” to retire from Zion, and to take a few years off from playing altogether, to travel and visit family and friends.

“It’s going to be different but at the same time I look forward to being in the pew, on the other side,” Heizer said. “I don’t have to worry about if singers are going to be sick. I don’t have to worry about problems, if a minister is going to show up. I can walk in, sit down, and when it’s over, get up and leave. There’s something to be said for that.”

Heizer, 75, freelanced at several churches while a student at Peabody. Zion felt right.

“I thought this would be good, this would be a little more experience, and I had not really planned to stay here for this long,” Heizer said. “I interviewed for some other jobs, but they weren’t exactly what I expected, so I just sort of ended up staying. And of course, I got myself established in Baltimore, and it’s hard to make a change, unless you have a really big position to go to.”

Pipe organs and churches have an obvious and natural reliance on each other. Baltimore churches employed many of Peabody’s students over the decades, providing them with a practical avenue for their art. The program once enrolled a robust 15 to 20 students. Ringkamp has only eight colleagues in his program. Likewise, the number of local pipe organ builders is much smaller.

Zion, like many other churches in the city, is suffering. It’s adapting to the effects of changing demographics, as churches in general play a smaller role in urban life. Suburban megachurches might be thriving, but as a country, the U.S. is less religious. A recent Gallup poll showed that religious service attendance remains low in the U.S. among most religious groups.

Urban congregations in Baltimore are in line with that trend, be they Lutheran, Catholic or Jewish. The story of Zion is similar to the story of Shaarei Tfiloh Synagogue by Druid Hill Park, or the many Catholic churches that are closing and consolidating in Baltimore.

Heizer’s decision to leave was also driven by the struggles of the church. Playing services to a mostly empty room without singers is simply less rewarding. The number of singers the church could afford to pay and how much they could offer kept shrinking.

Started to serve the German immigrant community, which fueled its membership for more than a century, Zion’s first major setback in attendance was after the outbreak of World War II, “when it was just really hard to be connected to a German church,” Deibler said. About half the membership left, she said. The riots of 1968 also set back attendance. The church leadership debated whether to relocate outside the city and ultimately decided to stay. But many of its members did not.

The pandemic took it over the edge, a fall the church has yet to fully recover from, leaving Deibler and her co-pastor and husband Eric Deibler to find the best path forward.

Zion depends on individual benefactors and income from renting the church and its adjoining social hall for events from concerts, weddings and film shoots. Its future depends on its connection to the immediate neighborhood, so the church has attempted to become a community resource with its “beer and brats” events, and serving as a cooling shelter for homeless residents, among other things.

Its German language service is something that sets apart Zion and is what drew Stephanie Peebles to her first service on Sunday.

Peebles, 63, was born in Germany and lived there as a young child because her father was stationed there in the Air Force. For a time, German was her primary language. She wants to avail herself of some of the German language classes the church still offers to those wanting to refresh or learn a language their parents or grandparents might have spoken.

But its German connection will not guarantee the church’s survival. Ironically, the language classes the church offered when it was a thriving place were for learning English.

“We’re really wrestling with that now,” Anke Deibler said. “What’s our mission now? Because helping Germans settle here is no longer it. Most of the Germans who come here now are perfectly bilingual.”

Ringkamp’s seat at Zion is temporary. He said he wants to study abroad next year. No matter who settles in at the seat of Zion’s pipe organ, their tenure is unlikely to last for 50 years.

If Heizer didn’t seem impressed at his own longevity, Peebles was. In addition to seeking classes, she made a point of coming to meet Heizer and congratulate him when she read about him on the church’s website.

“Anyone who does a job for 50 years,” she said, “deserves a lot of credit.”

Heizer’s playing days are not completely done. He said he will occasionally play the Wednesday service at Zion. And he might play at his own church, Grace & St. Peter’s Episcopal Church in Mount Vernon, where he will also continue to work as a bookkeeper.

“I’ll probably still maybe come here and practice some if they’ll let me, and I think they would,” he said, “but at this point, I just don’t have any big desire to do that right now.”