by the light of the heart

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When the body and mind grow weak, the Self gathers in all the powers of life and descends with them into the heart. As prana leaves the eye, it ceases to see. "He is becoming one," say the wise; "he does not see. He is becoming one; he no longer hears. He is becoming one; he no longer speaks, or tastes, or smells, or thinks, or knows." By the light of the heart the Self leaves the body by one of its gates; and when he leaves, prana follows, and with it all the vital powers of the body. He who is dying merges in consciousness, and thus consciousness accompanies him when he departs, along with the impressions of all that he has done, experienced, and known.

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As a caterpillar, having come to the end of one blade of grass, draws itself together and reaches out for the next, so the Self, having come to the end of one life and dispelled all ignorance, gathers in his faculties and reaches out from the old body to a new.

–Brihadaranyaka Upanishad

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