John Marco Allegro thought he had found a secret key. The problem was, no one would believe him.
In 01953, Allegro had been invited to the dusty shores of the Dead Sea to evaluate a newly unearthed trove of long-lost sacred documents — part of a team of respected British archaeologists brought to decipher one the greatest historical discoveries of the 20th century. The scrolls found there in the caves of Qumran had revealed a missing link in the evolution of Jewish spirituality, a rare and never-before-seen glimpse into the ancient world.
Allegro was soon assigned the work of translating a copper scroll that detailed the location of a vast treasure horde. But it was another hidden treasure that occupied his mind. Returning to Britain to study the documents in detail, he began constructing an elaborate theory based on hidden meanings he thought these ancient scrolls contained — a theory that would upend the entirety of sacred history.
Jesus, he believed, was a mushroom.
In 01970, amid a growing public debate about the powers (and legality) of psychedelics, Allegro released his thesis to the world in a book titled The Sacred Mushroom and the Cross. Analyzing the evolution of key Biblical terms from ancient Sumeria to the time of the Gospels, Allegro asserted that figures like Jesus, the story of his crucifixion, and the bread and wine of the Eucharist were nothing more than elaborate allegories for the use of psychedelic mushrooms.
“The names of the plants were spun out to make the basis of the stories, whereby the creatures of fantasy were identified, dressed, and made to enact their parts,” he wrote. “Here, then, was the literary device to spread occult knowledge to the faithful — to tell the story of a rabbi called Jesus, and invest him with the power and names of the magic drug.”
But their attempt to encode their psychedelic rituals behind the story of a Jewish rabbi had worked too well, Allegro said. “The ruse failed,” he wrote:
“What began as a hoax, became a trap even to those who … took to themselves the name of ‘Christian’. Above all they forgot, or purged from the cult and their memories, the one supreme secret on which their whole religious and ecstatic experience depended: the names and identity of the source of the drug, the key to heaven — the sacred mushroom.”
The Sacred Mushroom and the Cross was met with confusion, derision, and condemnation. Time magazine called it an “outlandish hoax,” an “erotic nightmare,” and the “psychedelic ravings of a hippie cultist.” Religious scholars scoffed at his labyrinthine etymologies and selective readings of biblical texts. “This book should be read as an exercise in how not to study myths and rituals,” one reviewer wrote. It was “possibly the single most ludicrous book on Jesus scholarship by a qualified academic,” the religious historian Philip Jenkins judged.
Today, Allegro’s theory is remembered as a quintessential example of academic suicide, like a Cambridge egyptologist suddenly confessing a belief in ancient aliens. He was soon forced to resign from his position at the University of Manchester. Amid a conservative backlash to the drug-fuelled counterculture of the ‘70s, his work faded into obscurity, a laughingstock remembered only by a loyal band of fringe conspiracists.
And yet, 50 years later, Allegro’s work suddenly seems oddly prescient. Enabled by a “psychedelics renaissance” brought on by increasing scientific experimentation with mind-altering substances, a growing body of scholars are arriving at the conclusion that psychedelics must have played a role in the evolution of human spirituality — and with it, the emergence of our very ideas about the nature of God.
Was Jesus a magic mushroom? Probably not. But God — well, that’s another story.

The academic study of psychedelics is barely a century old. Most trace its beginnings to the Swiss chemist Albert Hoffman, who first synthesized — and ingested — lysergic acid diethylamide, or LSD, in 01938. During the initial phase of cultural and scientific experimentation that followed, the job of researching psychedelics fell to an eclectic mix of psychiatrists, anthropologists, chemists, and journalists, many of them amateur investigators. Seldom did someone write about psychedelic substances without taking them and musing at length about the transcendent nature of the experience. It was a heyday for drug research, when the borders between disciplines dissolved as easily as the walls of a clinical observation room after a macrodose of mescaline.
At the same time, discoveries like the Dead Sea scrolls and the Nag Hammadi library, a collection of important writings from heretical Gnostic Christian sects, seemed to upend the consensus about the history of Western religion, including whether Jesus should be understood to be a real historical figure. For the largely Christian public of the time, the idea that there were secret, suppressed or undiscovered aspects of the faith was genuinely exciting — a translation of the just-discovered Gospel of Thomas, marketed as the “Secret Sayings of Jesus,” sold tens of thousands of copies in the United Kingdom alone.
For many of the writers of this experimental period, like Allegro, this combination unleashed the potential for a new revival of religion. “Millions of Americans, if they are ever to enjoy profound religious experience, will only do so through psychedelic drugs,” wrote Walter Houston Clark, a professor at Andover Theological School, in a 01968 editorial. He was only building on the writing of author and psychonaut Aldous Huxley, a decade earlier. “That famous ‘revival of religion,’ about which so many people have been talking for so long, will not come about as the result of evangelistic mass meetings or the television appearances of photogenic clergymen,” he wrote. “It will come about as the result of biochemical discoveries that will make it possible for large numbers of men and women to achieve a radical self-transcendence.”
But for many such thinkers, a New Age religion was not enough. They thirsted after evidence that psychedelics had always been present — that drugs were, in some way, the essential core of spiritual experience. “A mushroom is God’s signature,” wrote the psychedelics advocate John A. Rush, his “closest worldly condition.” For writers like these, proving some role for psychedelics in the Christian tradition was paramount. If it could be proven that the church was built on the foundation of holy fungi, not only would figures like Allegro be vindicated — psychedelics, too, could no longer be considered so taboo.
In the late 01970s, these writers believed they had found a smoking gun. A team including Hoffman, the classicist Carl Ruck and the celebrated journalist and ethnomycologist Robert Gordon Wasson published an investigation into an ancient Greek cult at Eleusis, known for its initiatic rite which saw participants come face-to-face with the gods by ingesting a mysterious drink known as the kykeon. It would “cause sympathy of the souls with the ritual in a way that is unintelligible to us, and divine, so that some of the initiands are stricken with panic, being filled with divine awe,” the Greek philosopher Proclus once wrote. “Others assimilate themselves to the holy symbols, leave their own identity, become at home with the gods, and experience divine possession.”

For Hoffman, Ruck, and Wasson, the descriptions of the kykeon and its effects were proof enough of an ancient psychedelic sacrament — likely ergot, they theorized, a fungus that grows on grain. The thesis, like Allegro’s, was largely rejected; but for Ruck, in particular, it was enough to suggest that psychedelic rites had informed the formation of the early Christian church. Eleusis was one of the most popular cults of the ancient world; its mysteries would have been familiar to the likes of John the Evangelist and St. Paul, who describes Christ’s own “mysteries” in similar terms in his epistle to the church at Corinth, just 40 miles from Eleusis. The cult was only suppressed — by Christian emperors — in the late fourth century, at the same time as the church was defining its own nascent orthodoxy.
Soon, Ruck was seeing mushrooms everywhere. Moses, he posited, was a psychedelic shaman, his encounter with the burning bush an allegorized mushroom trip. Paul’s conversion, too, was a “shamanic rapture,” his experience mirroring that of a psilocybin trip. The early Eucharist, he suggested, was an “ecstatic debauchery” like that at Eleusis, “anathematized in what became the official history of the transmission of the faith.” Even St. Catherine and St. Benedict were macrodosing fly agaric, a psychedelic mushroom, tripping far and wide from the seclusion of their monasteries.
Ruck’s theories were rejected by the mainstream scholarly world. “As perverse as it is unconvincing,” was the verdict of one reviewer. They also suffered from the misfortune of bad timing. By the tail end of the 01970s, the War on Drugs was ramping up, and psychedelics were firmly classed in the enemy camp. Soon, most mainstream academic research on psychedelics ceased. In the decades that followed, it was not so hard to imagine some ancient religious authority persecuting psychedelic sacraments to extinction — after all, it seemed, modern authorities were doing it, too.

Ruck’s ideas may have been an outlier in their grandiosity, but they weren’t without their fans. Forty years later, the thesis of Road to Eleusis was largely regurgitated by the American journalist Brian Muraresku, whose 02020 book, The Immortality Key, was an instant New York Times bestseller.
In explaining the rejection of theses like Ruck’s and Allegro’s, Muraresku blamed an ambiguous mix of ancient suppression — “a war for the soul of Western civilization” — and scholarly ignorance. “Forty years ago the Classics establishment was in no position to seriously consider the controversial marriage of the Mysteries and drugs,” he writes. “Let alone the possibility that the earliest Christians inherited a visionary sacrament from their Greek ancestors.”
At least where Muraresku is concerned, today’s “establishment” is not much more open-minded. Even leading psychedelic researchers like Jerry M. Brown rejected his book as little more than historical fanfiction. “In order to defend his central thesis, Muraresku executes a series of intellectual somersaults that are at best tenuous and at worst unsubstantiated,” Brown wrote in his review.
But in some ways, Muraresku is right to highlight the differences between now and then. Before the War on Drugs put psychedelic sciences on ice, a series of groundbreaking studies explored very real connections between psychedelics and the sacred — and a new generation of scholars is increasingly prepared to follow them up.
One of the turning points in psychedelic science came in 01962, when a PhD student named Walter Pankhe gave 10 theological students psilocybin — the active ingredient in magic mushrooms — and made them listen to the Good Friday sermon at Boston University’s Marsh Chapel. Almost all underwent transcendent religious experiences which, 25 years later, they still counted among the most meaningful spiritual experiences of their lives. One had to be restrained from running outside to announce the imminent return of the Messiah.
The now-infamous “Miracle in Marsh Chapel” proved that psilocybin and psychedelics like it could induce real spiritual experiences on par with those described by genuine mystics, the kinds that feature in the stories of religious figures we venerate centuries later. It posed a challenge to religious historians and theologians — largely unanswered by mainstream academia — to explain a role for psychedelics in the history of faith. As the theologian Ron Cole-Turner writes, “If the experiences [psychedelics] seem to induce are phenomenologically indistinguishable from the deepest experiences of the greatest mystics, then how can scholars in theology and religion simply dismiss or ignore them? Is that not willful ignorance of reality?”
The fact is, however, finding definitive historic proof of the use of sacred drugs has long posed a challenge for researchers. Set aside the fact that such substances would likely have been ingested in secret or reserved for a select few; they are all organic compounds, prone to breaking down. “This is the curse of archaeology,” the anthropologist Scott M. Fitzpatrick writes. “Many materials … simply do not preserve well over time except under exceptional circumstances.”
Still, emerging archaeological technologies have vastly expanded the ability of researchers to analyze finds for the chemical signatures that indicate the presence of psychoactive substances. “Archaeologists are now able to ask questions regarding human health and behavior that would have been unthinkable even a decade ago,” Fitzpatrick writes. And the result is a growing timeline of evidence — a lost history of drugs — that shows many centuries of psychedelics’ continuous use, even well into the Christian era.
As late as the fourth century, writers like Proclus and Plutarch were describing the existence of psychedelic sacraments around the ancient world. Egyptian priests were known to use eye ointments that engendered visions of the god Helios Mithras, and burned a psychoactive incense called kuphi that heightened their visionary powers. “It brightens the imaginative faculty [that is] susceptible to dreams, like a mirror,” Plutarch wrote. At pagan burial sites in Spain from roughly the same period, pottery remains show participants drank beer spiked with hallucinogenic nightshades, famous for inducing hell-like visions of the underworld.
Nor were sacred drugs reserved for pagans and polytheists. Recent archaeological excavations have revealed cannabis and frankincense residues at a 2,700-year-old Jewish temple in Tel Arad. The Torah names dozens of psychoactive substances, from wormwood to opium to datura. Danny Nemu, a psychedelics researcher, theorizes that the Holy Ointment mentioned throughout the Old Testament contained complicated mixes of substances that could induce religious experiences. The Tabernacle or Tent of the Congregation, used by the Israelites in exile, appears to be deliberately constructed as a smoke chamber for the Holy Incense, which shares properties with substances burned for the oracle at Delphi; Nemu calls it “the holy hotbox.”
These traditions built on some of the oldest expressions of religious devotion recorded anywhere in the world. The 4,000 year old Rig-Veda, and the equally ancient Zoroastrian Avestas, record a mysterious drug known as soma or haoma, called the “creator of gods” or “god of gods” and said to grant immortality. In 01968, Wasson identified soma as Amanita muscaria or fly agaric, a psychedelic mushroom, by comparing descriptions of its use and effects with the practices of Siberian shamans, whose own religion may well be descended from the same ancient Indo-Iranian root.
Even among the world’s oldest collections of neolithic cave art, deep in the highlands of the Algerian desert, there is evidence of what appears to be psychedelic sacraments. In the caves of Tassili n’Ajjer, you can find human figures engaged in a ritualistic dance, with strange mushroom heads and mushrooms in their hands. Even more striking is the figure known as Matalem-Amazar: a towering mushroom god, a humanoid figure encircled by — consumed by, constituted by — dozens of tiny mushrooms, emanating from their skin. The engravings are estimated to be more than 9,000 years old.

All this evidence adds up to a simple conclusion: “What is becoming clearer is that the use of mind-altering materials… is not relegated to a shallow period of time,” Fitzpatrick writes, “but goes deep into the ancient past.”
That has given rise to a controversial thesis that our capacity for religious sentiment may actually derive from our habitual use of drugs. After all, our species began as forest-floor foragers, in regions where psychedelic mushrooms grew plentifully in the dung of the very cattle they later domesticated. Like many other animals, we also seem to possess what the psychopharmacologist Ronald K. Siegel calls an “intoxication drive” — an impulse to seek inebriation in order to alter or expand our consciousness, equal to “the basic drives of hunger, thirst, or sex.” “Drug-induced alteration of consciousness preceded the origin of humans,” psychedelics researcher Giorgio Samorini writes. “It is an impulse that manifests itself in human society without distinction of race or culture; it is completely cross-cultural.”
As the researcher Michael Winkelman has suggested, psychedelic drugs also seem to act on a brain in a way uniquely suited to a mind developing new socio-cognitive functions. They relieve stress on the serotonergic system caused by socialization; they improve our “social mind,” our ability to collaborate and feel positive about others. Most importantly, they also seem to enable the rapid and significant rewiring of neural pathways. The physician Edward De Bono called this “depatterning” — the breaking out of the models our brain is bound to by language and by culture, essential for making cognitive and creative leaps.
For Winkelman, and for Fitzpatrick, all this suggests that psychedelics may have played a crucial role in developing many of our uniquely human capacities. “Continued scientific research is now demonstrating that those taxa with psychotropic properties have helped fuel social cohesion, led to the development of religious ideologies, and become the latticework in which social complexity arises,” Fitzpatrick writes. But the question is why this would give rise to religious sentiment in particular — why psychedelics so reliably give us, not just a creative experience, but a mystical one.
In the cognitive science of religion, the dominant explanation for the origin of the belief in gods has long been to blame a “hyperactive agency detection device”: in other words, an inclination, coded into our brain, to imagine threats where there are none — to imagine an active threat behind a rustling bush or bubbling water. But recent studies have challenged the viability of this explanation. Hyperactive agency detection is not correlated with religious belief, they say. Besides, our cognitive models are, ultimately, based on our embodied experiences. Why would we presume agency behind every undetermined stimulus, they ask, without past experience to inform our caution? And just how could our god-belief be so universally, cross-culturally encoded, if it is based on something we have never, in any capacity, experienced?
But what if God had already shown his face to us, had been here from the very beginning? What if God wasn't a man, or a power, or a hidden threat — what if God was, this whole time, a mushroom?

Now it is time for me to confess something. Since I was a child, I’ve had a crippling fear of mushrooms. I’ve abandoned entire restaurant meals, rather than pick out a few spongy chunks in a sauce. I struggle to even be near them. My mind is gripped by visions of their infinitesimal spores invisibly violating me, taking root in my flesh, in my blood. When I finally caved to spiritual curiosity and took magic mushrooms for the first time, I could only do so by telling myself, over and over again: “this is poison, yes, but you are poisoning yourself intentionally — this time.”
Part of my fear has long been rooted in a growing suspicion that mushrooms are not the lower life forms I had been taught to believe. A single fungal organism can live for thousands of years and span over miles. Their vast underground webs are largely invisible to us but communicate impossibly complex information we barely know how to decode. They are among the oldest life forms on earth, predating plants by more than 300 million years. Just what have they been up to?
Mushrooms not only trouble our theory of evolution by being so impossibly old — they challenge our dominant theories about why drugs come into existence at all. In theory, psychedelics are neurotoxins evolved to punish, not reward, consumption by animals. Why, then, do our brains seem to benefit from them so much? It’s a “paradox with far reaching implications,” one research team concludes.
One of the weird things about the mystical experiences occasioned by psychedelics is how universal and non-sectarian they tend to be. “It’s not uncommon for subjects to report encounters with symbols or deities that have not been part of their process of enculturation,” the pioneering psychiatrist William Richards writes in Sacred Knowledge, his book on psychedelic research. Midwestern atheists report seeing visions of Islamic architecture; Baptist priests hear Sanskrit liturgies in their ears. “When you get into the symbolic, archetypal realm… good agnostics are seeing images of the Christ,” he told me.
This goes some way to justifying the theory that our religious impulses may be born of these fungi, rather than simply activated by them. But such a conclusion, for the theologically inclined, would be revolutionary. What if our revelations — our relics, temples, and testaments — came not from God, but from an evolutionary dance with fungi? Can God still be said to exist if we accept that as true?
According to one line of thinking — a dominant one among cognitive scientists — the answer is likely no. Our “revelations” come from chemical reactions in the architecture of our brains; mushrooms are simply a stimulant for powers that reside, biologically, within us. This line of thinking builds upon a longstanding (though outdated) tradition in psychiatry to understand religion and spirituality as, in the words of Sigmund Freud, a kind of “universal obsessional neurosis,” a chronic disease of the brain.
The problem is, if religion is born of our habitual ingestion of a toxin, it is a kind of disease, a malfunction, a scar left behind by a foreign invader. This nags at me whenever I think about my psychedelic experiences and the kinds of feelings they engendered. When I’ve taken psilocybin, I’ve felt at one with nature and the earth. I have seen cosmic energy coursing up through the grass and the trees. All I want to do is lie content in the dirt, and let myself be totally consumed by it. Isn’t that exactly what a mushroom would want us to think?
For William James, the pioneering scholar in the psychology of religion, this was the main challenge posed by any mystic spirituality. “The problem [of] how to discriminate between such messages and experiences as were really divine miracles, and such others as the demon in his malice was able to counterfeit… has always been a difficult one to solve,” he wrote in his 01901 lecture on the varieties of religious experience. Which is the mushroom, then — an angel or a demon?
A growing number of Christian leaders are willing to defend the former proposition. Christian psychedelic societies and psilocybin retreats are becoming more commonplace. Theologians are starting to reckon with their implications for pastoral care. Jaime Clark-Soles, a Baptist minister and biblical scholar, writes that psychedelics can help challenge the dominant “logocentrism” of Christianity. She’s investigating the idea of using Holy Week, the high point of the Christian calendar, as a “container” for a psychedelic retreat that could engender meaningful spiritual transformations. “I’ve worked a lot with clergy with psilocybin,” Richards told me. “They start preaching without notes.”
Psilocybin used in this way could give rise to a “new Reformation,” a “popular outbreak of mysticism,” in the words of theologian Charles Stang — even, it would seem, a Christian one. Clark-Soles was quick to tell me the many ways in which the Bible celebrates the kinds of spiritual insights psychedelics can occasion: the unity of Creation, the power of love, the indestructibility and preciousness of life. But a psychedelic revival could just as easily undo traditional religion altogether. After all, in some ways, Christianity is an unparalleled celebration of the ego — a singular man, in history, who conquered sin and death.
It’s one reason why so many of the psychedelic mystics of the 01960s saw no hope in organized religion. “Western culture has, historically, a particular fascination with the value and virtue of man as an individual, self determining, responsible ego, controlling himself and his world by the power of conscious effort and will,” the writer and philosopher Alan Watts wrote in a 01968 essay. “Nothing, then, could be more repugnant to this cultural tradition than the notion of spiritual or psychological growth through the use of drugs.”
Somehow, some way, we seem to have left mushrooms behind — culturally, at least, if not within the architecture of our brains. Allegro saw this as the result of a vast historical conspiracy, a centuries-long effort to suppress the psychedelic faith of our forefathers. But perhaps it was something much more mundane. As our lives and societies became more complex, more evolved, we simply forgot the face of God. We mistook the revelations for the real thing. We looked for him in temples and in testaments, old and new. But we should have looked back where we, and he, started: in the shady undergrowth, where the fungi flourish.