"It seems logical that something was altered in people's consciousness. There are other stories in the Bible that mention the use of plants: for example, the tree of the knowledge of good and evil in the Garden of Eden," said Shanon. "The use of such substances, most of which fall in our contemporary Western culture under the label “drug," has in many traditions been considered sacred."
Professor Shanon argues that Israelites may have used acacia and peganum during religious ceremonies that involved DMT. Acacia is mentioned frequently in the bible, as it was used to construct the Ark of the Covenant.
Of course, all of this is based on the assumption that Moses actually existed. The Bible is simply not a reliable source of historical evidence. It is still a fascinating hypothesis as to why Moses would have experienced a burning bush that spoke to him as the voice of God.
What is likely is that someone had the experience with the burning bush, and a reasonable theory is that that person was on DMT.