When Metallica fans first heard the 1984 track “Creeping Death,” they might have been blown away by the band’s first use of a mass chorus.

They could also have been impressed by guitarist Kirk Hammett’s base riff, which started out in a song he’d written with his previous band, Exodus.

Most surprising of all might have been the discovery that this song was an exploration of the Jewish festival of Passover – and in particular, told the story of the Biblical moment that’s celebrated to this day. In the Book of Exodus (no relation, probably), the Passover is part of the 10th and final plague God unleashed in Egypt to persuade the Pharaoh to set Moses and the Children of Israel free.

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Anthrax guitarist Scott Ian explained the connection in the VH1 documentary Matzo and Metal: A Very Classic Passover in 2005.

“Metallica wrote a song about it, ‘Creeping Death,’” Ian said during a dinner with Twisted Sister’s Dee Snider and J.J. French, and Mountain’s Leslie West. “They were actually in Denmark recording Ride the Lightning, and they were watching The Ten Commandments. James [Hetfield] had seen it constantly on television. It’s the scene where Moses is bringing the plagues down on Egypt because the Pharaoh won’t let the Jews out of slavery.”

Watch ‘The Ten Commandments’ Passover Scene

Ian – who, along with his Anthrax colleagues, lifted the traditional Jewish folk song "Hava Nagila" for their 1987 comedy rap-metal single “I’m the Man” – recalled how the movie showed the process of “bringing the plagues down, one after another,” including thunderstorms, locust infestations and three days of darkness.

“The ‘creeping death’ is when God sends down the creeping fog that kills all the firstborn children,” Ian added, “and the Jews escape because they painted lamb’s blood on the doorway, so [the angel] knew to pass over their house.”

Impressed, the non-Jewish Snider responded: “‘Creeping death,’ Metallica, lamb’s blood – this is heavy metal!”

Late Metallica bassist Cliff Burton reportedly suggested the phrase “creeping death” when he saw The Ten Commandments. (In the Bible, the angel’s progress was entirely invisible, so the fog effect is purely theatrical.) Hetfield then developed the story from the angel’s viewpoint: “Slaves, Hebrews, born to serve to the pharaoh / Heed to his every word, live in fear / So let it be written, so let it be done / To kill the first born pharaoh son / I'm Creeping Death.”

Listen to Metallica Perform ‘Creeping Death’

'Creeping Death' Was 'Big Step' for Metallica

Hetfield later said this track, along with the rest of the album, represented a “big step” for the band. “When we did the crunchy 'Die by my hand' breakdown part in the middle, I sat in the control room after we did all the gang vocals, and everyone was just going nuts!” Hetfield told Guitar World. “That was our first real big, chanting, gang-vocal thing. There was almost some production value to it.”

Although parts of the Exodus song “Die by His Hand” eventually appeared in “Creeping Death,” Hammett said it wasn't through his own efforts.

“What I think happened was when Lars [Ulrich] and James were thinking about getting rid of Dave [Mustaine], our sound guy Mark Whitaker – who was Exodus’ manager – gave them Exodus’ demos,” Hammett told Rolling Stone. “I think ‘Die by His Hand’ might have caught their ears. So when they were writing ‘Creeping Death,’ they went, ‘Great. “Die by His Hand.” Put it right there.’

“It was definitely not me going, ‘I have a riff here in this Exodus song, and it needs to be here in this Metallica song,’” Hammett added. “By the way, I wrote that ‘Die by His Hand’ riff when I was, like, 16 years old.”

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