A Democratic nominee for Congress apologized on Monday after cursing during a debate at a synagogue on the previous day to represent Pennsylvania’s 1st Congressional District.

Scott Wallace and Rep. Brian Fitzpatrick stood on the bimah at Congregation Tifereth Israel in Bensalem, Pa., when Wallace used the “f”-word.

“I was exasperated by yet another attempt from Rep. Brian Fitzpatrick to hide from his votes to take away protections for people with pre-existing conditions,” said Wallace in a statement. “I apologize for any offense that might have been taken, I am passionate about protecting people from insurance company abuses, and I’m sorry that in this instance, my frustration got the best of me.”

The incumbent Fitzpatrick said he was “stunned” that Wallace made the comment.

“Ironically, there was a later question about the need for civility in politics,” Fitzpatrick told WBCB News. “Well, a good start is to not use vulgarities in the sanctuary of a synagogue in the middle of a congressional debate.”

As for his opponent’s motivations, “you’ll have to ask Scott Wallace,” said Fitzpatrick. “My sense is he was frustrated because I was cross-examining him on the ad he’s running, which is a false ad based on my position on pre-existing conditions. I was asking him a series of questions on what bill he was referring to, had he read it, and he came out with this expletive.”

Mort Lieberman, the men’s club president at Congregation Tifereth Israel, was not available for comment.

Wallace, who reportedly led a charitable foundation that donated to pro-BDS groups, leads his Republican opponent by 1.5 percentage points in the RealClear Politics average.