Andrew Hamblin handles poisonous snakes every Sunday in the name of Jesus. At just 22, he leads Tabernacle Church of God in LaFollette, Tenn., a Pentecostal church that practices a rare, century-old Christian tradition of worshipping God with venomous snakes like timber rattlers, cottonmouths, and copperheads. He plays mandolin, loves zombie movies, receives food stamps, has five children, and now is he is a star in a new 16-episode National Geographic reality series, Snake Salvation, premiering Tuesday about Appalachia’s serpent-handling churches.

The show is bound to stir interest in the unique—and mysterious—Christian sect. There are about 125 snake-handling churches in the United States, and almost all of them are found in Appalachia. Snake handlers like Hamblin do not worship snakes. Instead they use snakes to show non-Christians that God protects them from harm. In church services, when they feel the anointing of the Holy Spirit come upon them, these Christians reach into boxes, pick up poisonous snakes and hold them up as they pray, sing, and even dance. The belief comes from a literal reading of Jesus’ words at the end of the Gospel of Mark: “And these signs will accompany those who believe: in my name they will cast out demons; they will speak in new tongues; they will pick up serpents, and if they drink any deadly thing, it will not hurt them; they will lay their hands on the sick, and they will recover.”

Watch an exclusive clip from the series here:

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Spiritual signs like speaking in tongues, holding venomous snakes, and even drinking poison or playing with fire may seem radical to many Christians. All Appalachian states except West Virginia outlawed the snake-handling ritual when it first emerged because it too often left people maimed or dead. But for Hamblin, the practice is a part of Jesus’ teaching as much as the Sermon on the Mount. “As we say down here when we preach, it is written in red letter,” he explains, referring to Bibles that print the words of Jesus in red ink. “It is in my King James Bible, and that is what I go by, the King James Bible.”

Even within Christianity, the Bible passage in question is a point of controversy. Most scholars agree that the Bible’s editors added those verses to the original gospel text several centuries after it was written. Chronologically, the Gospel of Mark was the first of the four gospels, and the last twelve verses of Mark are absent from the two earliest manuscripts. Early third-century theologians like Origen and Clement of Alexandria also make no mention of them.

That does not deter devoted serpent handlers. “For scholars of religion, the questions surrounding the Mark 16:9-20 passage are extremely important for questions of canon formation and scriptural authority,” explains Yolanda Pierce, scholar of religion at Princeton Theological Seminary. “But for those who believe that the version of the Bible that they physically hold in their hands is the true, literal, and unchanging word of God, it’s pretty irrelevant if that particular Mark passage was added later than the other chapters.”

Believers like Hamblin find snake-handling to be a life-giving religious practice for several reasons. Ralph Hood, psychology of religion professor at the University of Tennessee at Chattanooga and an expert on the Christian snake-handling tradition, says that serpent handlers truly understand that nobody gets out of this life alive. “The issue is not whether you are going to die, but how you are going to die,” he explains. “They say they want to die being obedient to God.”

The spiritual reason for the practice runs deep. “In Christianity, the serpent has long been a symbol of death and resurrection,” Hood continues. “They literally in their ritual overcome what for the average person is the fear of death.”

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On a practical level, the ritual also creates a very strong sense of community. Part of that bond definitely derives from how much is at stake, says producer of “Snake Salvation” Matthew Testa, but it also comes from the radical life transformation many snake handlers have experienced. “There were a lot of people who had struggled with addiction, had been on the wrong side of the law, had been involved in drug dealing and crime, and really wanted to reform their lives, were really trying to live right as they would say,” Testa says. “They are people who came from an extreme background and feel the need for an extreme belief system to counterbalance the temptations their lives.”

The National Geographic show will undoubtedly raise questions for viewers. What bothers people about snake-handling, Hood explains, is that it is a high-risk behavior. “I’ve argued is that that is a bias, thinking that a religious ritual can’t involve risk,” he says. “In secular activities we allow all kinds of high risk behavior—you can ride a motor cycle, you can hang-glide, the injury rate in professional football is now [near] 100%.”

Testa agrees that the show will challenge people’s views about faith. People may find the practice unsettling, but the shows stars, including Hamblin, find comfort, reassurance and strength in the ritual. “Certainly someone who is critical of this religion could say, why would you want to risk your life for the words in the Bible on a regular basis and possibly die and desert your family and your loved ones and leave this earth?” Testa says. “I think when you see what the alternative is for these people, the way they see it, it’s either I do this and I stay close to God, or I backslide and I go way off back to the way I was, maybe overdosing, maybe back in jail. When those are the choices you feel are presented to you, it starts to make more sense.”

The series itself is just one part of Hamblin’s vision. His spiritual mission is big. One day he hopes to lead an international mega-ministry that goes far beyond snake-handling, one that would focus on “reaching out and feeding the hungry, helping homeless people, helping the drug addicts, seeing them be delivered, the alcoholics be delivered,” as he says.

For now he has one main concern for Snake Salvation viewers—he hopes people experience not just snakes, but God when they witness his church. “I do not want us to be ignorant, illiterate rednecks that holler, ‘For God so loved the world, let’s handle a snake!’” he says. “It doesn’t matter if you believe like me or do like me, as long as you get saved. I don’t care what anybody’s denominational belief is as long as they get saved by the blood of Christ.”

National Geographic’s new series Snake Salvation premieres Tuesday, Sept. 10, at 9pm EST.

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