The Taoist polymath Tao Hongjing subsequently compiled and redacted Yang's revealed texts into the c. 499 Zhen'gao (真誥, Declarations of the Perfected) compendium, which formed the foundations of the Shangqing School of Taoism.

Contrasting a simple medium who supposedly conveys information from a god or spirit, Yang Xi produced a comprehensive religious system with sacred scriptures, philosophy, and practices.

Furthermore, he was highly cultured, a superb calligrapher, and well-informed about the Chinese classics and Buddhist scriptures available in the 4th century[1] Few historical facts are known about Yang Xi's life, and most information comes from his own revealed texts.

[7] He was a disciple of Bao Jing (260-330), the teacher and father-in-law of Ge Hong, and of the Xu family Way of the Celestial Masters jijiu (祭酒, Libationer) Li Dong (李東).

In 367, Yang informed Xu Mi about Mao Ying's prophesy that in nine years he would be transferred from the earthly bureaucracy to begin his honorary position in the Shangqing Heaven.

He subsequently moved to Maoshan (茅山) or Mount Mao, about 15 miles southeast of the family home in Jurong, where he had erected a wooden jìngshì (靜室, Quiet Chamber) that served as his oratory for meditation and worship.

[14][15] Xu Mi introduced Yang Xi to the Prince of Langye (琅琊) Sima Yu (司馬昱, 320-372, later Emperor Jianwen of Jin), who employed him as both Household Secretary and Minister of Instruction.

[16] Between 364 and 370, Yang Xi had a series of midnight visions in which zhenren "Perfected Ones" from the Heaven of Shangqing Supreme Purity appeared to him in order to communicate both their sacred texts and personal instructions.

The revelations included jing (經, Scriptures), several zhuan (傳, Hagiographies) of the Perfected, and supplementary jue (訣, Instructions) about understanding and employing the texts.

Early readers of these revealed texts were impressed both by the erudite literary style of ecstatic verse and the artistic calligraphy of Yang Xi and Xu Hui.

[5] Although no autograph copies of Yang Xi's famous calligraphy have survived, one well-documented stone rubbing version of the revealed Huangting jing (黃庭經, Yellow Court Scripture) has been given special attention.

The Song dynasty connoisseur and critic Mi Fu (1051-1107) analyzed four manuscripts of the Huangting jing, and said the best one was written on a silk scroll with a provenance that he traced back to the early 8th century.

Mi disagreed with a former owner Tao Gu (陶穀, 903-970) who said that Wang Xizhi wrote the manuscript, and concluded it was a superb example of calligraphy from the Six Dynasties period.

The Ming dynasty calligrapher and painter Dong Qichang (1555-1636) was so impressed by the Mi Fu manuscript that he made a copy, recommend it as the best model for studying kaishu script, and included it as the first example in his classic Xihong tang fatie (戲鴻堂法帖, Calligraphy Compendium of the Hall of the Playful Goose).

Tao Hongjing compiled and redacted these transcribed revelation texts from 490 to 499, constituting the Shangqing scriptures that formed the basis of the school’s beliefs in new visualization- and meditation-based ways to reach immortality.

[27] The central apocalyptic message transmitted by Yang to the Xus was that they were among a chosen few people destined to survive the imminent destruction of the world, and to live on as members of the Perfected ruling hierarchy in the new age.

Much of the content in Yang's visions seems to derive from a variety of older sources, Taoist, Buddhist, scholarly, and popular, despite the "resplendent homogeneity which originally disparate elements appear to have acquired in his inspired transcriptions".

Tao's Daoist master Sun Youyue (孫遊岳, 399–489)—who had been a disciple of Lu Xiujing (陸修靜, 406–477), the standardizer of the Lingbao School rituals and scriptures—showed him some fragments of Yang Xi's and Xu Hui's original textual manuscripts.

[35] Using calligraphy as his primary criterion of authenticity, Tao Hongjing assembled a substantial corpus of autograph texts by Yang and the Xus, as well as a number of transcripts written by others concerning the same Shangqing revelations.

[41] Tao Hongjing's "Account of the Diffusion of the Yang-Xu Manuscript Corpus" (Zhen'gao 7) records a remarkable case of unauthorized copying, "amounting to a rabid, if idealistic, kleptomania".

[43] The story involves a talented scholar named Wang Lingqi 王靈期 who was envious of the great influence and wealth that Ge Chaofu attained from producing the Lingbao School Scriptures, and wanted to spread the Shangqing revelations to the public.

[44]This description of Wang Lingqi deviously increasing the "fees for transmission" refers to the Shangqing tradition that none of Yang Xi's revealed texts could be transmitted without the recipient swearing an oath of secrecy and paying predetermined quantities of precious metal and silk.

[47] In Shangqing traditional beliefs, any disciple who received a revealed document through authorized transmission had entered into "a bonded contract with the powers on high", and invested in "a sort of celestial security".

This created an extended community of Shangqing Daoists bound to one another in overlapping master-disciple relationships through oaths that supported the transmission of sacred texts, "possession of which conferred both identity and authority".

[50]Yang Xi was a regular user of marijuana, according to Joseph Needham and his Science and Civilisation in China collaborators, Ho Ping-Yü, Lu Gwei-Djen, and Nathan Sivin.

[53] The (c. 1st century BCE) Shennong bencao calls "cannabis flowers/buds" mafen (麻蕡) or mabo (麻勃) and says: "To take much makes people see demons and throw themselves about like maniacs.

But if one takes it over a long period of time one can communicate with the spirits, and one's body becomes light"[54] A 6th-century Daoist medical work, the Wuzangjing (五臟經, Five Viscera Classic) says, "If you wish to command demonic apparitions to present themselves you should constantly eat the inflorescences of the hemp plant".

[51] The Zhen'gao gives alchemical prescriptions for gaining visionary power, and Yang Xi describes his own reactions to using the Chushenwan (初神丸, Pill of Incipient Marvels) that contains much cannabis.

[53] Both Yang and Xu Mi were regularly taking Chushenwan cannabis pills that were supposed to improve health by eliminating the Sanshi (三尸, Three Corpses) from the body, but which also apparently brought about "visionary susceptibility".

[56] The (5th-6th century) Yuanshi shangzhen zhongxian ji (元始上真眾仙記, Records of the Assemblies of the Perfected Immortals), which is attributed to Ge Hong (283-343), refers to the Shangqing founders using qīngxiāng (清香, "delicate fragrance; purifying incense").