I’m not being a lawyer; I really don’t know Christians' answer to this.
It just seems to be an important question for a variety of reasons.
First, a definition: entheogens are safe botanical narcotic chemicals contained in some plants. An example is psilocybin in some species of mushroom, THC in cannibis, DMT in some vines (and in your brain, but more on that later), and so forth.
These chemicals have been used by shamans for years to communicate with spirits and to transcend this world in some profound way. Some, such as DMT, practically throttle users into mystical states. Many who have taken these chemicals, be they Muslim, hardcore atheist, or fundamentalist Mormon, speak of their worldviews being seriously challenged after having taken entheogens. When taken therapeutically, entheogens often have the effect of making users more open to empathize with people and consider their points of view.
Entheogens minimize ego.
Entheogens have been around for thousands, perhaps millions, of years.
So here are my questions to Christians:
Why would God create plants that would throttle people into mystical states?
Here’s why the question is important:
Religion always begins with emotion or felt experience. People don’t intellectualize which religion to choose. A good example is Francis Collins, famed mapper of the human genome and a Christian:
“Then one day in 1978, as he hiked past a glorious waterfall in Oregon's Cascade Mountains, Collins felt a stirring he could not resist. The next morning, he knelt in a meadow behind his motel and gave his life to Jesus.”
No intellectualization. No thinking. And yet you can’t completely dismiss his experience. He was overwhelmed by an emotion that told him Jesus Christ made that waterfall in the Cascades. Religion is borne from emotional experience and a sense of the mystical.
Now imagine ancient man on a food-gathering mission. He sees the sticky flowering tops of a wild female cannabis plant, grabs a few buds, chews one, and continues on his way. An hour later, this man has his first mystical experience”filled with terror and awe and an overwhelming sense of the supernatural. The cannabinois receptors on his brain, host to the cannabinoid molecule in the cannabis he just ate, does its work. Man realizes that God is trying to communicate with us not through error-riddled scroll and parchment, but through the very botany he created for man’s sustenance.
This is very likely how religion began. What say you?
(I think this is a problem for atheists, too, but I'd like to address that in another thread at another time.)