"What a long, strange trip it's been" may be known as a catchphrase conjured up by The Grateful Dead to describe their mind-expanding experience with psychedelic drugs in the 1960s. But a Hebrew University professor of psychology claims that it may also be an appropriate title for the journey experienced by Moses and the Israelites when they wandered in the desert for 40 years.

Writing in the British scholarly journal Time and Mind, Prof. Benny Shanon claims that Moses and the children of Israel were likely under the influence of natural psychedelics found in the Sinai Desert when cataclysmic events like the receiving of the Ten Commandments took place.

He writes that two naturally existing plants in Sinai have the same psychoactive components as one of the most powerful psychedelic substances in existence, the Amazonian brew Ayahuasca.

"One plant is Peganum harmala, harmal in Arabic, the other is acacia, shita (plural, shittim) in Hebrew; they contain betacarbolines and DMT, respectively," Shanon wrote in the study.

Shanon, who admitted that he had partaken of the Ayahuasca brew about 160 times while in the Amazon in 1991 and at later locations and times, wrote that he "experienced visions that had spiritual-religious connotations."

After extensive research into Biblical texts, he concluded that several key episodes in the life of Moses exhibited features that were prominent symptoms of the Ayahuasca experience.

"These episodes include Moses's first encounter with the Divine and the theophany at Mt. Sinai, traditionally regarded to be the most important event in all of Jewish history," he wrote.

Shanon, whose main focuses of research are the phenomenology of human consciousness and the philosophy of psychology, also wrote that the burning bush episode was likely the result of psychedelic hallucinations as well.

"In advanced forms of Ayahuasca inebriation," he wrote, "the seeing of light is accompanied by profound religious and spiritual feelings."

While in the Torah there are no indications of the use of the Peganum harmala, there is clear evidence that the second plant - acacia - was most valued, according to Shanon.

"From it were made the tabernacle and the ark in which the Mosaic Tablets of the Law were guarded. The acacia tree was also regarded as sacred by the ancient Egyptians," he wrote.

"In the Bible we discover clear indications that psychoactive plants were highly valued in ancient Israelite society.

Taken together, the botanical and anthropological data on the one hand, and the biblical descriptions as well as later Jewish hermeneutics on the other, are, I propose, suggestive of a biblical entheogenic connection," concluded Shanon.

"Admittedly, the smoking gun is not available to us. However, so many clues present themselves which, like the pieces of a jigsaw puzzle, seem to cohere into an intriguing unified whole," wrote Shanon, adding that his research had been conducted in a way similar to that of an independent detective's investigation.