"Swearin' to God" is a song written by Bob Crewe and Denny Randell. It was recorded by Frankie Valli and released in May 1975 as a single from his album Closeup. It's a love song whose lyrical hook is a more literal use of the expression "I swear to God" (i.e., "I mean this sincerely"):

The first Valli song to incorporate the disco style (it runs four minutes as a single but just over ten minutes on the album), "Swearin' to God" features Patti Austin singing a response to Valli's praise in the bridge. "Swearin' to God" hit number 6 on the U.S. Billboard charts and also charted #31 in the UK.

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