"Holy, holy, holy" they sang at the Church of St Timothy in Blaine, Minnesota.
But the congregation is struggling to comprehend an act of evil - the brutal murder of one of their own.
Melissa Hortman grew up here. The former state speaker and her husband Mark were shot dead in their home on Saturday morning.
Her friend and party colleague, Erin Koegal, was among those attending mass.
"It still feels like a bad dream. I woke up this morning and was like, okay, so that was real," she said.
"It's hit me in waves, the grief, and the anger, and the sadness. She was a leader, a true definition of a leader.
"I've never known our party without Melissa as the leader and so I can't, I don't even know how we're going to go forward as a caucus without her."
State senator John Hoffman and his wife Yvette had already been shot and wounded.
Police sent to check on his colleague, Melissa Hortman, didn't get there in time.
The suspect - 57-year-old Vance Boelter - was detained after a two-day manhunt.
Minnesota Governor Tim Walz called it a "politically motivated murder".
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Friends of Ms Hortman have told Sky News that her two children feared for their mother's life after reading divisive rhetoric directed at her online.
Matt Norris, another political colleague of Ms Hortman, was also at church, reflecting on the rise of political violence in America.
"We've going to have to do some serious introspection as a state, as a country, and figure out how do we get beyond this," he said.
"How have we been laying the seeds that have led to horrific acts of violence against public servants like this?
"And it's going to be incumbent upon us as leaders to set a different tone, to set a different direction for our state and our country so that horrific tragedies like this never occur again."
But there's no sign of division at the State Capitol Building, where flags fly at half-mast and flowers are being left in tribute.
This is a community united in grief and in its hope for an end to gun violence in America.
(c) Sky News 2025: 'It feels like a bad dream': Minnesota mourns victims of 'politically motivated assassination'
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