This is an article in two parts. The first part discusses current research in psychoactive preparations of ergot in various religious systems with a particular emphasis on Persian, Greek, Jewish and Islamic sources. Certain poems, hadith, and scriptural writings suggest an entheogenic heritage to various ancient sects that exerted and received philosophical and ritual influences over large distances and over time. Particularly, some esoteric Shia and Sufi writings are highly suggestive of a “celestial botany” that employed psychoactive plants for initiatory and ritual purposes. The second part will address current research methods that render ergot alkaloids nontoxic and entheogenic, a most crucial part of the discussion in the absence of a modem bioassay. This is essential, as without a chemical reality to support that such a preparation of entheogenic ergot is possible, all ergot theories concerning mystery traditions would remain largely speculative.