In traditional Chinese calendar systems, the heavenly stems and earthly branches play an important role. Among them, "Geng" (庚) as one of the ten heavenly stems is closely related to specific cultural customs and folk beliefs. This article will explore in depth the meaning of "heavenly stem is Geng" and the associated traditional customs and folk legends.
Definition of Geng Day
A Geng day refers to a day in the stem-branch calendar where the heavenly stem is "Geng." The stem-branch calendar is formed by combining the ten heavenly stems and twelve earthly branches, creating sixty combinations used to record years, months, days, and hours. Among the ten heavenly stems, "Jia, Bing, Wu, Geng, and Ren" are considered yang stems, and "Geng" is one of them. Therefore, it can only be paired with yang earthly branches, namely "Zi, Yin, Chen, Wu, Shen, and Xu," forming six Geng days: Gengzi, Gengyin, Gengchen, Gengwu, Gengshen, and Gengxu.
Geng Day and the Start of Heat
The third Geng day after the Summer Solstice is called "Rufu" (入伏), an important moment in traditional Chinese solar terms. On the day of "Rufu," it must be a Geng day, and "Rufu fears encountering Shen" means that if the day of "Rufu" is a Shen day, then it becomes a Geng Shen day. The Geng Shen day holds special cultural significance; according to folk legends, on this day, the "insects" inside the human body leave the body while people are asleep to report people's behavior to Heaven. Hence, there is a custom called "Shou Geng Shen" (守庚申), which involves staying awake all night on Geng Shen days to prevent the "insects" from leaving.
The Custom of Shou Geng Shen
"Shou Geng Shen" is a folk custom aimed at preventing the legendary "insects" from leaving the body through staying awake. Ancient records state that on Geng Shen days, people should stay awake all night. If they feel tired, they may take short breaks but must not fall into deep sleep. This custom reflects people's observations and understanding of natural phenomena and physical conditions, as well as their reverence for mysterious forces.
Dashu and Red Clouds
In long-term agricultural life, people found that if red clouds appear on the day of Dashu (Great Heat), it often indicates that extreme weather such as typhoons may occur soon. After Dashu comes a critical period for crop growth, and the destructive power of typhoons is great, possibly causing crops to fall over and affecting harvests. Therefore, there is a saying among the people: "Dashu fears red clouds," expressing concern about extreme weather and emphasis on the safety of crops.
The heavenly stem being Geng is not only a part of the stem-branch calendar but also embodies Chinese traditional culture and folk beliefs. The determination of Geng days, the customs of entering heat and observing Geng Shen, as well as the observation of Dashu and red clouds, together form a rich and colorful cultural picture, reflecting the profound understanding of ancient people about natural laws and their respect for the unknown world.
