"I Saw the Light" is a country gospel song written by Hank Williams. Williams was inspired to write the song while returning from a concert by a remark his mother made while they were arriving in Montgomery, Alabama. He recorded the song during his first session for MGM Records, and released in September 1948. The song is set to the tune of the traditional Scottish folk tune "Bonnie Charlie", also commonly known as "Will ye no come back again?". The song became the shows' closing song for Williams and one of his most popular tunes. Williams' version did not enjoy major success during its initial release. The song was soon covered by other acts and with time became a country gospel standard.

In September 1946, Hank Williams auditioned for Nashville's Grand Ole Opry but was rejected. After the failure of his audition, Williams and his wife Audrey tried to interest the recently formed music publishing firm Acuff-Rose Music. Williams and his wife approached Fred Rose, who signed him to a six song contract, and leveraged a deal with Sterling Records. In December 1946, Williams had his first recording session. The songs "Never Again" and "Honky Tonkin'" became successful, and earned Williams the attention of MGM Records. His first MGM session took place on April 21, 1947. The first song he recorded was "Move It on Over". The second was "I Saw the Light".

Williams was inspired to write the song in January 1947 while returning from a show in Fort Deposit, Alabama. His mother, Lilly, drove him and the band back to Montgomery that night. As she was approaching the city, she spotted the lights of Dannelly Field Airport. Williams, who slept inebriated in the backseat of the car, was roused by his mother, who told him "I just saw the light", announcing him that they were close to Montgomery. He wrote the first draft on January 26, 1947. The lyrics and the melody by Williams closely resembled Albert E. Brumley's "He Set Me Free", published in 1939 and released in March 1941 by The Chuck Wagon Gang.Biblical citations were used, including the Gospels of Matthew and John, as well as excerpts from the First Epistle to the Thessalonians and Book of Revelation. As Williams' biographer Colin Escott astutely observes, while the melody and even some of the lyrics bear a passing resemblance to the earlier Brumley tune, "'I Saw the Light' wasn't just 'He Set Me Free' with new lyrics, though. It was the prayer of the backslider, who lives in hope of redemption."

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