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A person’s growth begins with dissatisfaction. Not content with the world, he seeks satisfaction by prayers to God; this purifies his mind and he longs to know God more than to satisfy his carnal desires. Then God’s grace begins to manifest. God will take the form of a guru and appear to the devotee, to teach him Truth so that his mind gains strength and is able to turn inward. With meditation the mind is purified yet further, and eventually remains still without the least ripple. That stillness is the Self. The guru is both exterior and interior: from the exterior he gives a push to the mind to turn inward and from the interior he pulls the mind towards the Self. That is grace. See? There is no difference between God, guru and Self.
— Ramana Maharishi (1879-1950), South Indian mystic