Mysterium tremendum (Greek: "mystery that triggers fear and trembling") denotes the Divine as the cause and object of awesome trepidation.
The term was coined by the Protestant theologian and religious scientist Rudolf Otto in his main work Das Heilige, in order to describe an in his opinion irreducible moment of religious experience. The mysterium tremendum forms there a contrasting pair with the mysterium fascinosum, which is to describe the experience of religious delight: mystery tremendum et fascinans. The divine is always both at the same time: attractive and deterrent, captivating and menacing.
Both terms continue to play an important role, especially in Protestant theology and philosophy of religion. Since they are intended to describe the basic irrational experiences of religion, they are also used to distinguish themselves from a purely rational religion.
According to Rudolf Otto, both the mysterium fascinosum and the mysterium tremendum represent essential features and properties of the numinous. Edit source text
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