Of all the Philadelphia choruses, Singing City is the one most likely to pivot its forthcoming concert around the war in Ukraine.

Though classical music organizations find that concerts planned a year ago suddenly resonate with current events, the 7 p.m. May 7 Singing City program at the Philadelphia Episcopal Cathedral, titled “Seeking Peace in a Weary World,” has three great composers, spanning 200 years, writing music to the words “dona nobis pacem” (grant us peace).

“Like everything since the pandemic, we’ve become incredibly flexible in our thinking,” said executive director Lauren Hallquist-Anderson.

“But this is the first time we’ve shifted this quickly,” said longtime artistic and music director Jeffrey Brillhart.

Based at the Friends Center (the Quaker hub at 15th and Cherry Streets), the group has a deep-seated moral imperative built into its DNA with a history of tours to South Africa, Mexico, and other places where humanitarian statements needed to be made. “Artists have to have to ability to read the room, to know themselves and recognize their own truth and if their truth meshes with the community,” said alto Kerri Williams, from Pine Forge, at a recent rehearsal.

But not with what tenor Brian Auerbach from Philadelphia calls “false sweetness. The repertoire this group consistently picks ... requires reflection, as opposed to just veneer.”

And if ever a foreign war was personal, it’s this one: Out of 65 singers, nine have personal connections to Ukraine, some so close that they tear up when talking about it.

The concert’s original plan was to perform Paul Moravec’s 2017 oratorio, Sanctuary Road, based on the stories of the Underground Railroad. The already hired vocal soloists — tenor Aaron Crouch, soprano LaToya Lain, and baritone Malcolm J. Merriweather — also fit the Ukraine-centered program, with the total package staying within was the lean concert-production budget of $30,000.

The program, also featuring Chamber Orchestra of Philadelphia, evolved into a mixture that includes spirituals, a choral version of Samuel Barber’s Adagio for Strings plus the “Dona nobis pacem” works by J.S. Bach (1685-1750), Felix Mendelssohn (1809-1847), and Vaughan Williams (1872-1958), each composer coming from different sides of war.

Bach arose from an era still scarred by the Thirty Years’ War (1618–1648), his “Dona nobis pacem” from his Mass in B minor suggesting doors opening into a peaceful utopia, with constantly ascending vocal lines, pushed upward by muscular bass lines. Written when revolutions and uprisings were erupting from France to Russia, Mendelssohn’s 1831 Verleih uns Frieden offers a plea to government leaders “so that we under them may lead a calm and peaceful life in all godliness and respectability.”

The British-born Vaughan Williams was an ambulance driver in World War I and, in 1936 as war clouds were gathering in Europe once again, he pulled together his cantata Dona Nobis Pacem that is far from the amiable, pastoral works that the composer is best known for. Vaughan Williams’ “scrapbook” of texts (in the words of one scholar) was dominated by Walt Whitman’s brutal Civil War verse but also included biblical quotes from the Book of Jeremiah: “We looked for peace but no good came.”

All of the pieces could’ve been written for Singing City, whose late founder Elaine Brown described choral singing as “a natural, spontaneous medium for building understanding among people, and Singing City must take and make every opportunity to do so.” Such opportunities included self-financed tours of the Deep South during the most contentious years of the Civil Rights Movement, trips to the Balkan countries and, in 2019, to Mexico in response to the U.S. government’s condemnations of that country’s moral character.

With that kind humanitarian spine, the chorus attracts all manner of members, from seasoned professional singers to newcomer Sterling Randolph, a National Guardsman who lives in Quakertown, and admits that he doesn’t read music at all. But he sings with his father’s dying words in the front of his mind: " ‘Unite the world without bloodshed,’ " he said. “And that’s exactly what Singing City’s mission is.”

Lest we think it’s all high-minded sweetness and light, Brillhart is capable of tart directives, such as telling his singers that singing in tune “does not equal singing loud.” Singers themselves grumble as much as anyone over mask mandates that come and go in Philadelphia. For the May 7 concert, singers will take a rapid test and have the option to perform without a mask. Masks must be worn by the audience. “It’s surprising how much sound you can realize through a mask,” said Hallquist-Anderson, “but nobody wants to be doing it.”

Singing City’s “Seeking Peace in a Weary World“ is at 7 p.m. May 7 at the Philadelphia Episcopal Cathedral, 23 S. 38th St. Tickets: $37. Information: www.singingcity.org.