Novello created the character in 1973, after he purchased the outfit (consisting of big floppy black hat, white clerical collar, and a long, red-trimmed black coat with cape) for $7.50 at a St. Vincent de Paul Thrift Store. The character was featured in 1970s cartoons by the underground cartoonists Dave Sheridan and Fred Schrier, appearing in person in the early 1970s on Rowan & Martin's Laugh-In and later in the 1975 Smothers Brothers TV show. His most prominent appearance was on Saturday Night Live in the late 1970s, during which time Novello was also a writer for the show. In the late 1970s, Father Guido Sarducci was featured on radio commercials for High Times magazine where he offered to perform blessings for a fee.
On his first appearance on Saturday Night Live, a skit called "How to Pay for Your Sins" on a 1978 episode hosted by Richard Dreyfuss, he was on crutches from an injury suffered during a dress rehearsal sketch about hockey players. Most of his appearances on SNL have been on Weekend Update, including one where he reported that "The take at the shrines in Italy has gone down" which he suggested correcting by creating "Shrinemobiles" and thus taking the shrines to where the people were, and another where he is sent to London to try to wake up Paul McCartney at 4:30 in the morning (11:30 in New York) by throwing coins, obnoxiously singing The Beatles and Wings songs, and finally, throwing a rock at the window (he says it works every time). One of Sarducci's most memorable SNL pieces occurred on February 16, 1980, when he actually managed to corner Richard Nixon at 1 a.m. outside the former president's New York City home for an interview. A stunned looking Mr. Nixon did not respond to the one question that Sarducci managed to get out before the end of airtime: "Mr. President, Mr. President, if you coulda be any animal in the world, whata would it be?" Sarducci has appeared in four cold openings in the 1979–1980 season (on episodes hosted by Steve Martin, Teri Garr, Elliott Gould, and Rodney Dangerfield), two commercial parodies ("MX-5 Tampons" on the 1981–1982 Christmas episode hosted by Bill Murray and "Bocce Ball My Way" on the last episode of the 1985–1986 season hosted by Anjelica Huston and Billy Martin), and two monologues on the 1985–1986 season (the first hosted by Madonna in a pretaped sketch showing Madonna's wedding to Sean Penn (played by Robert Downey, Jr.) and the second on the Christmas episode of the 1985–1986 season hosted by Garr as Sarducci's alter ego, Pope Maurice). Sarducci also hosted two SNL episodes during the 1983-1984 season (when Dick Ebersol was executive producer) and cameoed during two 1990s episodes, most notably on a Weekend Update segment where he reports on Pope John Paul II's missing wallet. Father Guido Sarducci has 31 appearances on SNL, the most of any of the recurring characters.
In 1981 Novello made newspaper headlines when he visited Vatican City wearing the Father Guido Sarducci costume to do a photo shoot for Time magazine. After taking pictures in an area where photography was prohibited, he and his photographer, Paul Solomon, were arrested by the Swiss Guards and Novello was charged with "impersonating a priest". Although the guards attempted to confiscate the film from the shoot, Solomon managed to hand them the wrong film. The charges were later dropped. In the early 1980s, Novello was featured in ads promoting candidates for the priesthood. He listed one advantage of being a priest as getting first pick at the annual parish garage sale.
During the 1980s and 1990s Sarducci appeared on other television shows, including Fridays, Married... with Children, Unhappily Ever After, Blossom, It's Garry Shandling's Show, and Square Pegs. In 1980, Sarducci appeared in Gilda Live!, a film and an album recording based on Gilda Radner's successful one-woman show which had been playing on Broadway. In 1984, he appeared in a music video for the Jefferson Starship song "No Way Out". In 1995, he appeared as a priest trying to perform an exorcism in the movie Casper. The same movie featured a cameo by his fellow SNL alumnus Dan Aykroyd as the Ghostbuster Ray Stantz.
The character also appeared on the Handsome Boy Modeling School albums So... How's Your Girl? and White People, telling biographical stories of the life of a professional male model in the latter. Novello also released two comedy albums as Sarducci: Breakfast in Heaven and Live at St. Douglas Convent. He also appeared on the MSNBC show Countdown with Keith Olbermann on March 19, 2005, discussing The Da Vinci Code and his DaVinci Code Decoder Ring.
In Disney Studios' animated film Atlantis: The Lost Empire released in 2001, Don Novello uses the voice and speech style of Father Sarducci to portray the character of demolitions expert Vinny Santorini.