Religion: Jewish Catholic
Name: Jerry Costanza
Classification: supporting character based on a real person
First Appearance: Sleepwalker Holiday Special #1 (Jan. 1993): "Tricks of the Trade"
Creators: Tom Brevoort, Mike Kanterovich, Bruce Zick, Armando Gil
Number of Appearances: 1
Note: based on Jerry Sienfeld and George Costanza
Jerry Costanza is based on the characters Jerry Sienfeld and George Costanza from the popular television sitcom Sienfeld. The "character" of Jerry Sienfeld is a non-observant Jew, as is the same-named actor who plays him. (Sienfeld essentially played a fictionalized version of himself in the TV series.) The character of George Costanza is a lapsed Catholic. Larry David, the co-creator of Sienfeld once stated in an interview that Larry David that George is half-Jewish and half-Italian. The character of George Costanza is based on Larry David himself, as portrayed by and significantly influence by the actor who plays him: Jason Alexander. Larry David and Jason Alexander are both Jewish. The Marvel Comics character of "Jerry Costanza" is based on a Jewish character and a Jewish Catholic character. For this reason, Jerry Costanza can be classified as Jewish Catholic. The character's religious affiliation was not actually addressed in this Marvel comic book story. This identification draws on facts outside the actual published story.
Suggested links for further research about this character and the character's religious affiliation: