The prohibition on alcohol under Islamic Sharia law, which is usually attributed to passages in the Qur'an, dates back to the 7th century. Although Islamic law is often interpreted as prohibiting all intoxicants (not only alcohol), the ancient practice of hashish smoking has continued throughout the history of Islam, against varying degrees of resistance. A major campaign against hashish-eating Sufis was conducted in Egypt in the 11th and 12th centuries resulting among other things in the burning of fields of cannabis.[citation needed]
Though the prohibition of illegal drugs was established under Sharia law, particularly against the use of hashish as a recreational drug, classical jurists of medieval Islamic jurisprudence accepted the use of hashish for medicinal and therapeutic purposes, and agreed that its "medical use, even if it leads to mental derangement, should remain exempt [from punishment]". In the 14th century, the Islamic scholar Az-Zarkashi spoke of "the permissibility of its use for medical purposes if it is established that it is beneficial."[4]