Question: When I start to go deep within, I feel sleepy.

Sri Chinmoy: It is not sleep; you are making a mistake there. While you are meditating, your mind is entering into the world of calmness and silence. There you don't have to create any movement or be dynamic. This world of silence is not like ordinary sleep, where one becomes totally unconscious. On the contrary, it is a very good state. Try only to grow into that state with utmost sincerity, humility and devotion. However, if meditation proper has not yet taken place, if you feel sleepy when you are merely preparing to meditate, it means that inertia and sloth are present. But if it is after a good meditation that this feeling comes, it is not sleep at all. You are entering into the world of silence and mistaking it for sleep.

From:Sri Chinmoy,Meditation: God speaks and I listen, part 2, Sri Chinmoy Lighthouse, 1974
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