"I Walk the Line" is a song written and recorded in 1956 by Johnny Cash. After three attempts with moderate chart ratings, it became Cash's first #1 hit on the Billboard charts, eventually reaching #17 on the US pop charts. The song remained on the record charts for over 43 weeks, and sold over two million copies. It has also been used on many LPs released from Sun Records, such as With His Hot and Blue Guitar, Sings the Songs That Made Him Famous, and Sings Hank Williams. It was the title song for a 1970 film starring Gregory Peck and a 2005 biopic of Cash starring Joaquin Phoenix. The song captures Johnny Cash's "boom-chicka-boom" sound by Johnny putting a dollar bill in the neck of his guitar. Background of the song The unique chord progression for "I Walk the Line" was inspired by the backwards playback of guitar runs on Cash's tape recorder while he was stationed in Germany as a member of the United States Air Force. Later in a telephone interview, Cash stated, "I wrote the song backstage one night in 1956 in Gladewater, Texas. I was newly married at the time, and I suppose I was laying out my pledge of devotion." After writing the song, Cash had a discussion with fellow performer Carl Perkins, who encouraged him to adopt "I Walk the Line" as the song title. Cash originally intended the song to be a slow ballad, but producer Sam Phillips preferred a faster arrangement; in the end, Cash agreed to the change, and the uptempo recording met with success. On one occasion, while performing "I Walk the Line" on his TV show, Cash explained to the audience the reason for his humming during the song: "People ask me why I always hum whenever I sing this song. It's to get my pitch." The humming was necessary since the song required Cash to change keys several times while singing it. The song's lyrics discuss resisting temptation, being accountable, and remaining faithful to Vivian Liberto during his first marriage. However, Johnny Cash would eventually divorce Vivian Liberto and then marry June Carter. Vivian Liberto would write a book called "I Walked the Line" about her time with Johnny. "I Walk the Line" was originally recorded at Sun Studio on April 2, 1956, and was released on May 1. It spent six weeks at the top spot