We all know that Moses was high on Mount Sinai when God spoke to him, but were the Ten Commandments a result of divine inspiration alone?

An Israeli researcher is claiming in a study published this week the prophet may have been stoned when he set the Ten Commandments in stone.

According to Benny Shanon, a professor of cognitive psychology at the Hebrew University of Jerusalem, psychedelic drugs formed an integral part of the religious rites of Israelites in biblical times.

Writing in the Time and Mind journal of philosophy, he says concoctions based on the bark of the acacia tree, frequently mentioned in the Old Testament, contain the same molecules as those found in plants from which the powerful Amazonian hallucinogenic brew ayahuasca is prepared.

"The thunder, lightning and blaring of a trumpet which the Book of Exodus says emanated from Mount Sinai could just have been the imaginings of a people in an altered state of awareness," writes Shanon. "In advanced forms of ayahuasca inebriation, the seeing of light is accompanied by profound religious and spiritual feelings."

References in the Bible where people "see" sounds, is another "classic phenomenon", he said, citing the example of religious ceremonies in the Amazon in which drugs are used that induce people to "see" music.

Speaking about his article on Israeli public radio, he added: "As far as Moses on Mount Sinai is concerned, it was either a supernatural cosmic event, which I don't believe, or a legend, which I don't believe either. Or finally, and this is very probable, an event that joined Moses and the people of Israel under the effect of narcotics."

Moses was probably also on mind-altering drugs when he saw the "burning bush", suggested Shanon, who admitted to dabbling with such substances.

Speaking of his own experience of ayahuasca during a religious ceremony in Brazil's Amazon forest in 1991, he said: "I experienced visions that had spiritual-religious connotations."