Here's a passage from the Record of Linji that I have finished translating today. This comes from near the end of the untitled Part One. Various translators insert their own titles like "Discourses" or "Ascending the High Seat," but since the text itself does not have a title for the beginning section which is the largest section, I have not added one. Part Two is titled "Examining Differentiation" and Part Three is titled "Record of Travels."
The Record of the Words of Zen Master Linji Huizhao of Zhenzhou.
Collected by Huiran, a minor teacher of the inherited Dharma, dwelling at Sansheng.
"Turn the light around and shine it on yourselves" is a colloquial way of describing the technical term asraya-paravrtti which means to "turn around or turn back to the seat, basis, or resting place" of what we call the light of knowing, consciousness, or awareness.
Variations of the phrase "turn the light around and shine it on yourselves" are now well known in Western Zen communities. Whether sitting, standing, walking, or lying down, this is the essential method of practice in Zen and the common denominator of all Zen lineage schools. This central teaching is found in the works of most of the Zen masters, such as in works after Linji of Dogen's 13th c. "Fukanzazengi or Rules for the Universal Recommendation of Sitting Meditation," and Hakuin's 18th c. "Zazen Wasan or Song of Zazen," as well as in works before Linji such as the 8th c. Chinese Zen foundational text The Platform Sutra of the Sixth Ancestor Huineng and Sengcan's famous 6th c. Zen verse "Inscription on Faith in Mind." Asraya-paravrtti or "return to the basis" is found as the phrase "return to True Suchness" and "return to the root" in the important 6th c. work <大乘起信論> "Treatise on the Mahayana Arousing of Faith" translated into Chinese by the Indian scholar-monk Paramartha.
Before the Zen Masters of China asraya-paravrtti was a staple of Indian Masters such as the 4th c. half brothers Asanga and Vasubandhu, as found in the later's "Trimsika-Karika or Thirty Verses." At its earliest appearance it was given canonical authority in the Mahayana Sutras espousing the One Vehicle or Ekayana such as the Lankavatara Sutra or The Sutra of Going Down to Lanka, and The Sutra of Queen Srimala's Lion's Roar.
Without the actual experience of turning the light around to shine it upon ourseves, our understanding remains at the intellectual level only. To Mahayanists, asraya-paravrtti is the true meaning of the purification (visuddhi) espoused by the Early Schools, because in returning the light of awareness to its source or fountainhead, the contrived dualistic delusions are cast off and the purity of not-two is realized. Thus Linji said "Buddha is the mind's purity." As Zen Master Hui Hai said, this is "the ultimate purity" because "it is a state of beyond purity and impurity."