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Symbolizing the functions that impede our progress towards enlightenment, T'ien-t'ai explains, "As practice progresses and understanding grows, the three obstacles and four devils emerge in confusing form, vying with one another to interfere...One should be neither influenced nor frightened by them." THESE are the three obstacles.
What are 1) the obstacle of earthly desires, 2) the obstacle of karma (negative actions committed in this life) , and 3) the obstacle of retribution (negative effects of our past lives)?