The relationship between psychedelics and religion isn’t new: the ritual use of psychoactive substances has been documented for millennia around the globe. More recently, scientific inquiry has informed how we think about psychedelics and spirituality. What do altered states of consciousness tell us about humankind’s religiosity?

In 1962, a Harvard Divinity School graduate student named Walter N. Pahnke gathered a group of 20 volunteers. Half were given psilocybin, and half received an active placebo. Then, the participants attended a Good Friday service. Almost all of the members of the psilocybin group reported profound religious experiences—which they described as one of the high points of their spiritual lives 25 years later.1

The Good Friday Experiment was significant because it illustrated an unexpected intersection between science and religious experiences: altered states of consciousness. But how do religious experiences change how people think—and what role do psychedelics play?

The History of Psychedelics and Religion

Before we talk about psychedelics and religion today, we need to take a trip back in time—specifically, sometime around 7000 to 5000 BCE.

Tassili, Algeria, features one of the earliest indications of spiritual drugs: cave paintings depicting, among other illustrations, shamanic figures decked with mushrooms. Some scholars believe the paintings are evidence of a hallucinogenic mushroom cult.2

In an article about psychedelic use in world religions, Michael Winkelman notes that there are parallels between shamanism and psychedelic experiences, including ego death, dissociation, and hallucinations. In some societies, shamans consumed entheogens (psychoactive drugs used in ritual or religious contexts) to enhance their mystical experience while surrounded by community members. This practice may have influenced the evolution of human religious beliefs.3

Psychedelics have a history of ritual use in medicinal contexts, too. For example, peyote is a religious sacrament for Indigenous people in North America, and ceremonies are usually called for healing. The cactus has been used for thousands of years, as indicated by prehistoric cave paintings in Texas and California.4

The altered states of consciousness that spiritual drugs promote are deeply tied to the way premodern societies interacted with their communities and thought about the world around them. Entheogens shape the foundation of many religions that persist today, such as peyotism in the Native American Church and Ayahuasca use among Indigenous peoples in and around the Amazon basin.

Deep Psychedelic Spiritual Experiences

In 2019, researchers surveyed individuals with God-encounter experiences. They split the respondents into two groups: those who had encountered God with and without using psychedelics.5

In both groups, most participants reported vivid memories of the experience and communion with an all-knowing being. Half of the participants had complete mystical experiences, defined as feelings of unity, interconnectedness, sacredness, and transcendence, among other attributes.6

This study was notable for a few reasons: it was the first of its kind to compare God-encounter experiences between psychedelic and non-drug users, and it demonstrated how experiences of this magnitude could shift a person’s beliefs.

More than two-thirds of people who identified as atheists before their God-encounter experience no longer identified as atheists afterward. Plus, the experiences contributed to positive changes in their life satisfaction, purpose, and meaning.

The following year, researchers surveyed people about their most memorable entity encounters after taking DMT.7 What’s an “entity?” One of the common effects of DMT is interacting with a seemingly autonomous entity, sometimes described as a being, guide, alien, or elf.

As with the 2019 study on God encounters, more than half of people who identified as atheists before the experience no longer identified as atheists afterward. DMT and religion might seem like mutually exclusive concepts. Still, this study added to the idea that mystical experiences can profoundly influence a person’s sense of life satisfaction, purpose, and meaning—whether or not the experience is drug-related.

Here are a few quotes from participants who encountered DMT entities:

  • “I learned that when I resist uncomfortable emotions, I am selling myself short of the possibility to learn and grow.”
  • “It was on a personal level as I had been struggling with addiction of opiates at the time. She basically told me that I really needed to cut it out of my life because all it will bring is pain. I had not previously thought negatively about my use of opiates before this encounter.”
  • “The insight I received was that everyone and everything is connected.”
  • “There was an indescribably powerful notion that this dimension in which the entity and I convened was infinitely more ‘real’ than the consensus reality I usually inhabit. It felt truer than anything else I’d ever experienced.”

What Does the Science Say?

For all we know about the brain, consciousness remains a mystery. EEGs and fMRIs can show us brain activity. However, scientists are still studying the mechanisms behind how the brain processes information and turns it into subjective experiences like love, pleasure, and transcendence.

Part of the complexity is that consciousness isn’t confined to one brain region. For example, the cerebral cortex is important for memory, thinking, and learning functions, and the default mode network is related to your sense of self and future thinking.8,9

That said, one prevailing theory explains the mystical experiences psychedelics cause. Classical psychedelics act on the brain’s serotonin 5HT2A receptors, which are responsible for the hallucinatory effects of certain molecules; these receptors influence your mood, vision, and sense of self, among other effects.

Psychedelics increase serotonin activity in the brain by binding to 5HT2A receptors, triggering intense changes to your consciousness.10

Emerging research associates psychedelic mystical experiences with long-term positive changes. For example, studies have found that high doses of psilocybin improved mood and behavior that lasted months after treatment.11,12

Is Religion With or Against Psychedelics?

Some scholars believe many religions have historical ties to psychoactive substances, ranging from soma in Hindu scriptures to visionary plants in early Christianity. However, it isn’t easy to pin down what these substances are. Here’s an overview of prevailing theories in two major religions.

Christianity

Are there psychedelics in the Bible? In 1970, John Marco Allegro stewed major controversy upon the publication of his book The Sacred Mushroom and the Cross. Allegro proposed that early Christianity was an Amanita muscaria fertility cult and that Jesus never existed—he was simply a metaphor for the mushroom.

But since then, scholars have identified evidence of mushrooms in Christian medieval art, such as a fresco showing Adam and Eve in the Garden of Eden with a serpent coiled around (what looks like) an Amanita muscaria mushroom.13

In The Psychedelic Gospels, authors Jerry B. Brown and Julie M. Brown suggest that psychedelics and Christianity go hand-in-hand: for example, based on medieval illustrations, they argue that that the trees of knowledge and immortality in the Garden of Eden were sacred mushrooms.

Hinduism

Ancient Hindu scriptures, dating back to 1500 BCE, reference a psychoactive substance called soma, a plant associated with immortality and communing with deities. There are several theories about soma’s botanical identity: it may have been cannabis, opium poppy, ephedra, Amanita muscaria mushroom, or Nelumbo nucifera, among other possibilities.14

Final Thoughts

The historical ties between psychedelics and religion remains controversial. However, contemporary studies show the effects of psychedelic-occasioned mystical experiences can be indistinguishable from religious experiences. Psychedelics aren’t the only way to shift a person’s perception of themselves and their relationship with the world, but they’re fascinating tools—and perhaps played a role in the relationships with gods and higher powers in early societies.