The He Tu San Yuan Yang Xie Yi 太上洞神太元河图三元仰谢仪

Compiled and revised by Du Guangting, a Taoist priest of the late Tang and Five Dynasties period.

It is a one-volume work included in the Rituals and Ceremonies Section of the Cave Divine Division of the Daozang (Taoist Canon).

The preface of this book first expounds the essential purport of the Three Primes Thanksgiving Fast, claiming: "The Supreme Lord bestowed the River Map and the Dragon-Tortoise Scripts, inscribed with blue texts and green-shell characters, upon the emperors. These are precisely the methods to teach the people to invoke blessings, atone for transgressions, overcome adversities and dispel disasters." Whenever a state suffers from disasters such as wars, floods and fires, is plagued by evil spirits and monsters, when emperors and sovereigns are afflicted with unease, and even when the common people fall into emergencies, Taoist priests can be invited to perform this River Map Thanksgiving Fast ritual, offering gratitude to heaven and earth to mystically move the vault of the sky, thereby overcoming adversities and dispelling disasters.

The main text is divided into nine chapters, detailing the complete set of procedures and methods of the fasting ritual, from the erection of the altar hall and divine thrones to the completion of the sacrificial ceremony. The sequence of the ritual is as follows: 

1. Altar Hall; 2. Divine Thrones; 3. Entering the Altar; 4. Contemplating the Gods; 5. Offering Incense; 6. Igniting the Ritual Furnace; 7. Worshipping the Thirty-Two Heavens; 8. Repenting and Praying; 9. Closing the Ritual Furnace.