But this is exactly what Lucy Britner did when she saw two men trying to steal from the collection bowl.
The 30-year-old soprano was half-way through a Mozart rendition in the Unitarian Church in Brighton, when she spotted the dishonest duo.
Because everyone else was facing her, Lucy was the only one to witness the would-be crime.
But she was determined the church wouldn't be robbed and so she leapt from the stage, shouting: "What are you doing?" before chasing down the aisle to recover the stolen £150 of donations.
The religious robbers fled the scene empty-handed and got away, despite over 70 congregation members, including one off-duty police officer, pursuing them.
However, despite the commotion, Lucy still managed to finish her performance.
The food and drink journalist told the Mail Online: "It was unnerving, but I had spent months practicing those songs and there was no way I wasn't going to carry on."
Well, they do say the show must go on!
By Francesca Specter
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