Xishengjing
The Xishengjing (Chinese: 西昇經; pinyin: Xīshēngjīng; Wade–Giles: Hsi Sheng Ching; literally "Scripture of Western Ascension") is a late 5th century CE Daoist text with provenance at the Louguan 樓觀 "Tiered Abbey" of the The Northern Celestial Masters. According to Daoist tradition, Louguan (the eastern terminus of the ancient Silk Road, west of the capital Chang'an) was near where the legendary Laozi 老子 transmitted the Daodejing to the Guardian of the Pass Yin Xi 尹喜. The Xishengjing allegedly records the Daoist principles that Laozi taught Yin Xi before he departed west to India.
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