Top jockey Frankie Dettori opened the "Paddy Power Sin Bin" at St. Etheldreda's Church in Newmarket, southeastern England, where he married his wife Catherine in 1997, Sky News reported.
"It's a great idea, the community here needed some help and this is a good idea," he said.
Expensive refurbishment work at the church was being paid for by sponsorship from the Irish gambling company.
Parish priest Father Michael Griffin said, "You should never look a gift horse in the mouth. It's thought-provoking and maybe it will result in a few more people dropping in to say, 'Hello'."
Newmarket is the home of British flat racing, and the church was long seeking ways of building a better relationship with its racing community.
Worshippers at morning Mass discussed its arrival.
One man hailed the idea as "brilliant" and an elderly woman said, "Judge not lest you be judged yourself".SIC: NCAU