The Dao of Highest Clarity (shangqingdao 上清道) or School of Highest Clarity (Shangqingpai 上清派), also called the school or line of of Mt. Maoshan (Maoshanpai 茅山派, Maoshanzong 茅山宗) is one of the oldest Daoist traditions. "Shangqing" is the name of a celectial palace. Mt. Maoshan was the seat of its patriarchs. It began to spread with the compilation of the Shangqingjing 上清經 "Scripture(s) of Highest Clarity" during the mid-Eastern Jin period 東晉 (317-420).

According to Li Bo's 李渤 book Zhenxi 真系 (quoted in the Daoist encyclopedia Yunji qiqian 雲笈七籤) and Tao Hongjing's 陶弘景 Zhengao 真誥, these scriptures originated in the hands of Wang Bao 王褒, called Xicheng zhenren 西城真人 "Perfect Man of the Western City". Wang Bao transmitted his teachings to Wei Huacun 魏华存, the wife of a certain Liu Wen 劉文 from Jijun 汲郡. Wei Huacun became an immortal fairy and was later venerated as the wife of the Southern Peak 南岳夫人 (Nanyue furen), spouse to the Zixu yuanjun 紫虛元君 "Primordial Lord of the Purple Voidness". She is said to have descended from from Heaven in the year 364 and handed over the set of writings to Yang Xi 楊羲 (331-386), who was a retainer of a high official at the court of the Prince of Langya 琅瑯王. These writings were 31 juan "scrolls" of scriptures on the Highest Clarity, biographies of immortals, and miscellaneous precepts fort he cultivation of conduct. Yang Xi brought these scriptures into human wording and transmitted it to Xu Mu 許穆 or Xu Mi 許謐 (305-376) from Danyang 丹陽, and the latter to Xu Hui 許翽 (341-370). Xu Hui's son Xu Linqu 許臨沮 ordered Xu Huangmin 許黄民 (361-430) to collect ancient writings on talismans and secret commands and obtained these in 402. Ma Lang 馬朗 and Ma Han 馬罕 revised this collection. At that time, there was a Daoist practicioner called Wang Lingqi 王靈期, who, together with his collegues, asked to be granted a copy of these writings. Wang brought these scriptures into a refined language and also seemed to have increased the text corpus so that the product of his editing work was more than 50 chapters long. This corpus was the canon of a new Daoist school. Yet Yin Sheng 殷盛, a disciple of Xu Huangmin, called this product a forgery and instigated a long-lasting internal quarrel about the orthodox scriptures. Later on, his writings were known to Lu Xiujing 陸修静, a master of the school of the Southern Celestial Masters 南天師道, who integrated the Shangqing corpus, along with the Lingbao "Numinous treasure" writings 靈寳經 and the Sanhuang "Three Emperors" writings 三皇文, to the so-called "Three Caverns" (Sandong 三洞). His bibliography Sandong jingshu mulu 三洞經書目錄 was the fundament oft he traditional corpus of Shangqing writings. Lu handed over the writings of the "Three Caverns" to his disciple Sun Youque 孫游岳 (398-489), and the latter tot he famous Daoist writer Tao Hongjing 陶弘景 (456-536). In 488 the Shangqing scriptures were transmitted to the Daoist communities on Mt. Maoshan 茅山, where they were enlarged by more than 10 juan.

Tao Hongjing himself soon entered the community there and adopted the title of Huayang yinju 華陽隱居 "Hidden scholar of the South". Tao Hongjing expanded Gu Huan's 顧歡 book Zhenji 真迹 and described in detail how the Shangqing tradition as revelated and developed into a new school. These desriptions are to be found in a chapter of his book Zhengao. He also compiled the book Dengzhen yinjue 登真隱訣 to describe the methods of the Shangqing school. Because Tao Hongjing as the most important master of the Shangqing school resided in Mt. Maoshan, the Shangqing school is also called the Maoshan line. Another writings by Tao Hongjing is Zhenling weiye tu 真靈位業圖. Because of his systematisation oft he Shangqing canon, Tao Hongjing is often seen as the real founder of the school. He was venerated by Emperor Wu of the Liang dynasty 梁武帝, who granted him the title of Shanzhong zaixiang 山中宰相 "Counselor within the mountains". Tao's canonic title is Master Zhenbai 貞白先生. His disciple Wang Yuanzhi 王遠知 was a teacher to Emperor Yang 隋煬帝 (r. 604-617) of the Sui dynasty 隋 (581-618) and also enjoyed the patronage of the Tang 唐 (618-907) emperor Gaozong 唐高宗 (r. 649-683). Emperor Xuanzong 唐玄宗 (r. 712-755), who was generally inclined to Daoism, venerated the Maoshan patriarchs and the Maoshan Daoist Wu Yun 吳筠, who is also known as a famous poet. During the Song period 宋 (960-1279), the court was more inclined to support the Zhengyi school 正一道, but the patriarchs of the Maoshan Line never wholly lost imperial patronage, and especially the 25th patriarch Liu Hunkang 劉混康 enjoyed the support by the Emperors Zhezong 宋哲宗 (r. 1085-1100) and Huizong 宋徽宗 (r. 1100-1125). Emperor Shizong 元世宗 (i.e. Qubilai Khan, r. 1260-1294) of the Yuan dynasty 元 (1279-1368) also supported the various Daoist schools and granted the 44th and 45th patriarch the honorific title of zhenren 真人 "perfect man". The Maoshan Daoist Du Daojian 杜道堅 was granted an audience by Emperor Shizu. The Daoist writer Zhang Yu 張雨, also an adherent oft he Maoshan school, was the last great personality of this tradition before it lost ist preeminent position in the late 14th century.

The earliest sacred writing of the Shangqing school is the 39 chapters long Shangqing dadong zhenjing 上清大洞真經. It was postulated that reading this book ten thousand times would directly lead to immortality. In the Daoist Canon Daozang 道藏, this book is 6 juan long. This version is the product of a revision by the 38th patriarch Jiang Zongying 蒋宗瑛 from the Southern Song period 南宋 (1127-1279). Jiang is said to have ascended to Heaven into the land of Highest Clarity (Shangqing), a realm with a higher position than the Heaven of Greatest Clarity (Taiqing 太清), to which the adherents of the Heavenly Masters school (Tianshidao 天师道) ascended. The Shangqing school departed from the former practice of incantations and drunking talisman ashes. Instead, it focused on the cultivation of the "inner landscape" (neijing 内景) of the body by concentrating on the inner spirits and the circulation of energy (xing qi 行气). The concept of contemplation on the inner spirits (cunsi 存思 or cunxiang 存想) is a typical method of cultivation and refining (xiulianfa 修煉法). It appears first in the book Huangting neijing jing 黄庭内景經 that was compiled during the Three Kingdoms 三國 (220-280) or the Jin 晉 (265-420) period. The Huangtingjing is a very important writing concerning the understanding of the concept of zang 臟 and fu 腑 viscera in Chinese medicine. The book says that all vessels and organs in the human body are controlled by deities or spirits (shen 神), and it is necessary to contemplate about the existence and the effects of these spirits in order to preserve and nourish them. For practicing, the Huangtingjing is far too abstract and also includes errors concerning the treatment, but it is an important collection of early knowledge about the relationship between the parts of the body and the outer world, mainly sun, moon and the 24 starry constellations. The essence of these spirits hast o be preserved inside the body, and the spirits should not spread out.

The seven deities oft he Shangqing school are: Yuanshi xu huangtian zun 元始虚皇天尊, Taishang yuchen tadao ji 太上玉晨大道君 Taiwei tiandi dadao jun 太微天帝大道君 Housheng xuanyuan shangdao jun 后圣玄元上道君 Shang xiang qingtong dao jun 上相青童道君 Shang zai zong zhen dao jun 上宰总真道君 Xiao you qing xu dao jun 小有清虚道君 The line oft he oldest patiarch is 1) Wai Huacun, 2) Yang Xi, 3) Xu Mu, 4) Xu Hui, 5) Ma Lang, 6) Ma Han, 7) Lu Xiujing, 8) Sun Youque, 9) Tao Hongjing, 10) Wang Yuanzhi 王遠知, 11) Pan Shizheng 潘師正, 12) Sima Chengzhen 司馬承禎, 13) Li Hanguang 李含光, 14) Wei Jingzhao 韋景昭, 15) Huang Dongyuan黃洞元, 16) Sun Zhiqing 孫智清, 17) Wu Fatong吳法通, 18) Liu Dechang 劉得常, 19) Wang Qixia 王栖霞, 20) Cheng Yanzhao 成延昭, 21) Jiang Yuanji 蔣元吉, 22) Wan Baochong 萬保沖, 23) Zhu Ziying 朱自英, 24) Mao Fengrou 毛奉柔, 25) Liu Hunkang 劉混康, 26) Da Jingzhi 笪淨之, 27), Xu Xihe 徐希和, 28) Jiang Jingche 蔣景徹, 29) Li Jinghe 李景和, 30) Li Jingying 李景瑛, 31) Xu Shoujing 徐守經, 32) Qin Ruda 秦汝達, 33) Xing Rujia 邢汝嘉, 34) Xue Ruji 薛汝積, 35) Ren Yuanfu 任元阜, 36) Bao Zhizhen 鮑志真, 37) Tang Zhidao 湯志道, 38) Jiang Zongying 蔣宗瑛, 39) Jing Yuanfan 景元範, 40) Liu Zongchang 劉宗昶, 41) Wang Zhixin 王志心, 42) Zhai Zhiying 翟志穎, 43) Xu Daoqi 許道杞, 44) Wang Daomeng 王道孟, 45) Liu Dabin 劉大彬 (around 1300). The Maoshan Line of patriarchs is continuing today. The book Zhu zhenzongpai zongbu 諸真宗派總簿 lists branches oft he Shangqing school, named after the Three Masters of Mt. Maoshan (sanmao 三茅), namely the Qingwei school 清微派, the schools oft he second Mao 二茅派, the Jingyi school 靜一派, and the Gaoshang school 高上派. There is also a Yanzu school 閻祖派 that emerged in the late 17th century. This school was founded by Yan Xiaofeng 閻曉峰 who as actually a master of the Longmen school 龍門派 oft he Quanzhen line 全真宗. With his taking over the patriarchy oft he Maoshan school, the Quanzhen and the SHanging schools merged into one modern Daoist tradition. The earliest teachers of the Shangqing schools were all members of the gentry and possessed a high education. They were therefore able to attract the interest of the aristocracy and found many adherents among the upper class and at the court. This tendency was supported by the discarding of „primitive“ practices like the use of talismans (fulu 符箓), fasting rituals (zhaijiao 斋醮), the consumption of outer alchemist materials (waidan 外丹) and the art of the bedchamber (fangzhongshu 房中术). The popular religion of early Daoism had become attractive for all parts of society. The Shangqing or Maoshan school was venerated by all emperors, but especially during the Sui and Tang periods.