Love had to be inaugurated in the lowest form as sex-love, in order to rise through the various stages and finally, when the perfected Earth has reached its last epochs, to be imprinted into man as pure, spiritual love. All lower love is schooling for the higher love.
Source: Rudolf Steiner – GA 102 – The Influence of Spiritual Beings Upon Man: Lecture VI – Berlin, 24th March 1908
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