Michael Quirke, the education director of the Liverpool Comedy Trust said that initially the show was supposed to be held on July 8.
But they discovered that this would clash with the Jewish faith's three weeks of solemnity that begins on the sixth so they brought the date forward.
He added: "Rather than teaching them how to tell jokes, Chris and R David have been encouraging them to write their own material about life and present it more as observational comedy."
Gillian Miller, Chair of the Liverpool Comedy Trust added: "It's going to be a fantastic event -
it's a unique way of celebrating the wide range of diverse faiths we have in the city."
The project - one of 80 funded by Liverpool City Council's Creative Communities grant - aims to celebrate humour within the city's diverse communities as part of Faith in One City, the second Capital of Culture themed year.
Sir Bob Scott, Chairman of Liverpool's Capital of Culture Company, said: "The search is over for our Comical Catholic, and now the stage is set for a wonderful evening of holy hilarity."