170. the use of opium ... any substance that induceth sluggishness and torpor # 155This prohibition of the use of opium is reiterated by Baha'u'llah in the final paragraph of the Kitab-i-Aqdas. In this connection, Shoghi Effendi stated that one of the requirements for "a chaste and holy life" is "total abstinence ... from opium, and from similar habit-forming drugs". Heroin, hashish and other derivatives of cannabis such as marijuana, as well as hallucinogenic agents such as LSD, peyote and similar substances, are regarded as falling under this prohibition.
Abdu'l-Baha has written:
As to opium, it is foul and accursed. God protect us from the punishment He inflicteth on the user. According to the explicit Text of the Most Holy Book, it is forbidden, and its use is utterly condemned. Reason showeth that smoking opium is a kind of insanity, and experience attesteth that the user is completely cut off from the human kingdom. May God protect all against the perpetration of an act so hideous as this, an act which layeth in ruins the very foundation of what it is to be human, and which causeth the user to be dispossessed for ever and ever. For opium fasteneth on the soul so that the user's conscience dieth, his mind is blotted away, his perceptions are eroded. It turneth the living into the dead. It quencheth the natural heat. No greater harm can be conceived than that which opium inflicteth. Fortunate are they who never even speak the name of it; then think how wretched is the user.In one of His Tablets Abdu'l-Baha has stated concerning opium: "the user, the buyer and the seller are all deprived of the bounty and grace of God". In yet another Tablet, Abdu'l-Baha has written:O ye lovers of God! In this, the cycle of Almighty God, violence and force, constraint and oppression, are one and all condemned. It is, however, mandatory that the use of opium be prevented by any means whatsoever, that perchance the human race may be delivered from this most powerful of plagues. And otherwise, woe and misery to whoso falleth short of his duty to his Lord.
Regarding hashish you have pointed out that some Persians have become habituated to its use. Gracious God! This is the worst of all intoxicants, and its prohibition is explicitly revealed. Its use causeth the disintegration of thought and the complete torpor of the soul. How could anyone seek the fruit of the infernal tree, and by partaking of it, be led to exemplify the qualities of a monster? How could one use this forbidden drug, and thus deprive himself of the blessings of the All-Merciful?It should be noted that the above prohibition against taking certain classes of drugs does not forbid their use when prescribed by qualified physicians as part of a medical treatment.Alcohol consumeth the mind and causeth man to commit acts of absurdity, but this opium, this foul fruit of the infernal tree, and this wicked hashish extinguish the mind, freeze the spirit, petrify the soul, waste the body and leave man frustrated and lost.