I wasn’t expecting anything special on my Shabbat morning visit to Congregation Chevra Thilim, an Orthodox synagogue in San Francisco’s Richmond District. I was just going to services at a new place, right?

But, as I was reminded once again, every synagogue, every service, every ritual moment turns out to be interesting — if your eyes and ears are open to it and you ask the right questions. What I found was a shabbily breathtaking sanctuary; a small, but overwhelmingly friendly congregation; and a unique system of Torah trope hand signals (more on that later).

Chevra Thilim was founded in 1892, as it says on the ornate metal gate outside the current building. It moved there in the ’30s — from an  original location in the South of Market area — and with the exception of the sanctuary, the entire facility has been recently renovated.

Known as simply “Chevra” to regulars, the synagogue has an interesting origin story. It was founded by a group that gathered in the morning to recite psalms before services. Hence the congregation’s unusual name: Chevra refers to a group of friends, while Thilim (pronounced “tuh-hillum”) means psalms. (Rabbi Shlomo Zarchi told me he regularly hears “shevra thillum” from the uninitiated.)

I arrived a little late, but just in time for one of my favorites, Hallel, a series of psalms recited in the morning on joyful holidays, including Hanukkah, which was still going on that morning. Ever since I was a kid, I’ve loved the upbeat chanted melodies that go with Hallel.

When I visit unfamiliar communities, the selection of Hallel melodies is more or less the same, but at Chevra Thilim, more than half were new to me — a welcome surprise. At first, I found it a little off-putting; after all, I love the tunes that I know. But I shook myself of that liturgically narrow mindset as the congregation sang a rousing rendition of Mah Ashiv (Psalm 116) to the tune of the Hanukkah classic “Ma’oz Tzur” (“Rock of Ages”).

The sanctuary at Chevra Thilim, a little tattered and frayed at first glance, is actually marvelous. It’s a high-ceilinged room with wonderful morning light coming in through frosted side windows. The balcony has had the seating torn out and appears to be used for storage. At the front, a wide, high bimah has midcentury wood paneling along the walls and the plain, curving ark.

Above the ark is the real star of this space: a mural running the full width of the bimah and featuring a transporting, atmospheric image of striking mountains in brown and purple jutting up through layers of dramatic cloud. A sea-green sky flecked with stars is visible through a gap in the clouds, and a shaft of light from on high beams down on the mural’s centerpiece — the tablets of the Ten Commandments, of course.

I loved the space despite — or because of? — its decades-old, lived-in aesthetic, but there is one drawback: Nowadays it may be too big for the number of Shabbat morning regulars. The week I visited, there were perhaps 20 on the men’s side, with the vague silhouettes of seven or eight women on the other side of the semi-transparent curtain and half-wall running down the middle of the sanctuary. About a dozen little kids spent most of their time elsewhere, but did join us intermittently to run around or mill about.

This is a community of around 160 families who clearly know and have a high degree of comfort around each other. Many, Zarchi told me, are not Orthodox but come for the warmth or the top-notch shmoozing at the Kiddush luncheon. Some are even members of other synagogues, such as Conservative Congregation Beth Sholom, he said. The way he talks about it, you can tell Zarchi is proud of the shul’s openness and diversity of congregants.

I was offered an aliyah during the Torah service, which brought me in close contact with by far the most interesting thing I saw that morning. As Zarchi read from the Torah, the gabbai (a lay leader who reads along in a printed text, with full vowels and trope markings, helping the Torah reader avoid mistakes) was charismatically executing a remarkably crisp, forceful series of hand signals. Clearly this was a way of helping the reader maintain accuracy while chanting, but I’d never seen anything like it. I just stood there through my aliyah, grinning like an idiot and staring at the gabbai’s hands.

Later I asked Zarchi if it was a standard thing that I’d just never seen before. “Absolutely not,” he replied. “Everybody asks me about it.”

Evidently he and the gabbai, synagogue president David Kimmel, invented this system themselves. Kimmel pounds his fist downward for this trope, jabs two fingers upward for that one, etc. He stays a word or two ahead of Zarchi, who knows the trope well enough that this system serves mainly as a fail-safe. The trick, the rabbi said, is actually for Kimmel to keep up with him, not the other way around as one might expect. “He really enjoys doing it,” Zarchi said. “It’s like our own pitcher-catcher system [of hand signals], just for the two of us.”

And Zarchi was moving at a breakneck pace when I visited. A rare confluence of events called for three separate Torah scrolls to be used for three separate readings: one for the week’s Torah portion, one for the Hanukkah Torah portion and a third one for the Rosh Hodesh (beginning of a new Hebrew month) reading.

While I was on the bimah, Kimmel asked Zarchi if he was going to say a few more words between this aliyah and the next, as he’d been doing up to that point. He decided not to, saying, “We have more words than time this week.”