mystery religion

Any of various cults of the ancient world that were open only to the initiated; for example, the cults of Demeter (see Eleusinian Mysteries), Dionysus, Cybele, Isis, and Mithras. Underlying some of them is a fertility ritual, in which a deity undergoes death and resurrection and the initiates feed on the flesh and blood to attain communion with the divine and ensure their own life beyond the grave. The influence of mystery religions on early Christianity was considerable.

The earliest known mysteries, from at least as early as 1875 BC, are those connected with the legend of Osiris in Egypt. The ancient Greeks had many local mystery rites, and the Dionysiac and Orphic mysteries (see Orphism) were practised in various parts of the Hellenic world. In the 2nd century BC, on the break-up of the Alexandrian Empire and the beginning of the Graeco-Roman period, there was a revival of mystery religions, which exerted influence upon one another. The cult of Mithras (see Mithraism) belongs to this period.

In Christian theology, a mystery is something that cannot be known by human reason unaided by revelation, and that even when revealed transcends human comprehension; for example, the Trinity. The Eucharist has been called the Holy Mysteries, partly because of its sacramental character and partly because in the early church the unbaptized were not admitted to the whole of it.