A speculative hypothesis is presented according to which the ancient Israelite religion was associated with the use of entheogens (mind-altering plants used in sacramental contexts). The hypothesis is based on a new look at texts of the Old Testament pertaining to the life of Moses. The ideas entertained here were primarily based on the fact that in the arid areas of the Sinai peninsula and Southern Israel there grow two plants containing the same psychoactive molecules found in the plants from which the powerful Amazonian hallucinogenic brew Ayahuasca is prepared. The two plants are species of Acacia tree and the bush Peganum harmala. The hypothesis is corroborated by comparative experiential-phenomenological observations, linguistic considerations, exegesis of old Jewish texts and other ancient Mideastern traditions, anthropological lore, and ethnobotanical data.