Instead of studying the ideas of God and religion, Otto undertook to analyze the modalities of the religious experience… He succeeded in determining the content and specific characteristics of religious experience.
This passage establishes the phenomenological program — following Otto — of analyzing the sacred as a mode of lived experience rather than doctrinal content, the methodological foundation for the entire Eliadean corpus on the sacred.
, The Sacred and the Profane: The Nature of Religion, 1957thesis