We may say that there is hidden within man a being that keeps careful watch and ward on the boundary which has to be crossed at the entrance to the supersensible world. This spiritual being, hidden in man, which is man himself, but which he can as little perceive with ordinary consciousness as the eye can see itself, is the guardian of the threshold of the spiritual world. We learn to recognise him at the moment at which we are not only actually he, but are also confronting him, as though we were standing outside him, and he were another being.
Source: Rudolf Steiner – GA 17 – The Threshold of the Spiritual World: VIII: Concerning the Guardian of the Threshold
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