Historically, mind altering drugs have been used in pagan religious ceremonies for eons. God, however, prohibited the use of such substances by those who want to worship him. For example:
Gal 5:19 Now the works of the flesh are manifest, which are these; adultery, fornication, uncleanness, lasciviousness,
Gal 5:20 Idolatry, witchcraft, hatred, variance, emulations, wrath, strife, seditions, heresies,
Gal 5:21 Envyings, murders, drunkenness, revellings, and such like: of the which I tell you before, as I have also told you in time past, that they which do such things shall not inherit the kingdom of God.
See the word in red? The word translated "witchcraft" is actually the greek word:
pharmakeia
Thayer Definition:
1) the use or the administering of drugs
2) poisoning
3) sorcery, magical arts, often found in connection with idolatry and fostered by it
4) metaphorically the deceptions and seductions of idolatry
This is of course where we derive our english word "pharmacy". Pagan practices have never had a place in God's kingdom.
Another way I know that this is true is that I used to smoke pot. At the time I smoked I didn't see anything wrong with it. In fact, for years after I stopped I longed to smoke it again. But of course that's the drug, and Satan, working. Once I became a Christian, it was very apparent exactly what marijuana is.
A counterfeit form of religious that doesn't require God. Ask yourself why most Godless liberals are all for legalizing and smoking dope and why all the legalization efforts are spearheaded by leftists.
I suspect you won't be satisfied with my answer. There is no definitive way to prove a spiritual matter other than the physical results it brings.