Sheryl CrowSheryl Crow wrote it as a political song about national redemption. Johnny Cash took it and transformed it into his own, achingly vulnerable song about personal redemption. It's called 'Redemption Day' and first appeared on Sheryl's 1996 self-titled, sophomore album. The singer-songwriter remembers when the legendary Man in Black recorded it for his album, 'American VI: Ain't No Grave,' just three months before he died in September 2003. He would frequently call her on the phone, seeking to tap into the emotions that moved her to write such lyrics.

Sheryl says it was more than just the greatest moment of her musical career. "Actually, that's the highest honor I've ever had of anything in my whole life," Sheryl tells Glamour magazine (quote via CMT). "Him calling me and asking me, 'What were you thinking when you wrote this?' And him telling me about what it meant to him ... that was a true testament to him as an artist, wanting to be able to deliver a song and understand what it meant."

Though she wrote 'Redemption Day' so long ago, Sheryl says she still feels the same emotion she did when recording it in 1996 as she does when she listens to Johnny's haunting version, released seven years after his death.

"If he was going to sing a song, it was going to be a part of his molecular makeup," Sheryl tells Reuters. "He was going to deliver it as if he wrote it. The questions that he asked and his concern for whether I would like what he was doing ... it was just really humbling."

'American VI: Ain't No Grave' was released just three days before Johnny would have turned 78, in February 2010. The critically acclaimed album debuted at No. 3 on Billboard 200, selling 54,000 copies in its first week.

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