In both Taoism and Buddhism, the term turning the light around means turning the primary attention from involvement in mental objects to focus on the essence or source of mind. This exercise is practiced as a means of clearing consciousness and freeing awareness.
Dogen’s backward step (from Fukanzazengi)
Therefore, put aside the intellectual practice of investigating words and chasing phrases, and learn to take the backward step that turns the light and shines it inward. Body and mind of themselves will drop away, and your original face will manifest.
Jigme Lingpa’s verse
Then, when conceptual thinking arises,/Don’t look at what arises: be what knows the arising./Like an oak peg in hard ground,/Stand firm in awareness that knows,/And go deep into the mystery. tr. by Ken McLeod In The Trackless Path, 3.9
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