“Thy plants are an orchard of pomegranates, with pleasant fruits; camphire, with spikenard,
Spikenard and saffron; cane and cinnamon, with all trees of frankincense; myrrh and agarwood, with all the chief spices”
Not only are nearly all of the plants listed here in the Song of Songs psychoactive on their own, but the combination of some of them into the anointing oil reveals that the ancient Hebrews were very adept at working with synergies to trigger incredibly powerful mind-blowing experiences.
To facilitate a conversation with God, the Israelite High Priest would burn a mixture of finely ground psychoactive resins, on hot coals by the handful in a tiny and well-sealed room. This and other evidence suggests that they had advanced knowledge about techniques of mind-expansion.
The vision at Mount Sinai is distinguished by the fact that the people see sounds, whereas normally they hear them. It is also collective, whereas other visions appear to individuals:
“And all the people are seeing the voices, and the flames, and the sound of the trumpet.”
This is also the point in the Bible where the entire tribe is eating manna.
Manna appears to be psychoactive, and its physical description closely matches an ergot infection. Converting ergot to LSD is a simple operation well within the capabilities of the Israelite priesthood, given their extensive knowledge of psychoactive plants.