The Four Values gong cao are the four small gods of the heavenly court that are believed in Taoism, namely, month, day, and hour, which are equivalent to the duty gods of the celestial realm.

The functions and deeds of the Four Values gongcao are recorded in many Ming and Qing novels.
For example, in the fifth episode of "Journey to the West", after Sun Wukong made a big fuss about the Peach Victory Society and escaped from the Heavenly Palace, the Jade Emperor was very angry, and ordered the Four Heavenly Kings, Tota Li Tianwang, and the Three Princes of Nezha to pluck the Twenty-Eight Houses, the Nine Obsidian Star Jun, the Twelve Yuanchen, the Five-Party Revelation, the Four Values Gong Cao, the Five Yues and the Four Defilements, etc., lay down a heavenly net, and arrest the demon monkey. Among them, the fourth value of Gong Cao was not a stormtrooper, but a special merit for the generals, but the demon monkey had a great power, making Gong Cao useless, and later finally remembered a merit for the Erlang God, because he took sun monkey.
In the thirty-second "Pingdingshan Gongcao Passed on the Lotus Cave Mumu Disaster", Gongcao became a woodcutter and sent a message to the Tang monks and apprentices to prepare them to deal with the monsters. It can be seen that in addition to serving as a meritorious official, the four-value Gong Cao also acts as a guardian deity.
In journey to the West, the Four Values gong cao and the apologetics Jia Lan, Liu Ding Liu Jia, Wu Fang Jie, etc., secretly protected the Tang monks on the orders of Guanyin Bodhisattva. Whenever Sun Wukong was not with Tang Monk and Tang Monk was in trouble, they became the protector of Tang Monk. In fact, among the four values of Gong Cao, the daily Gong Cao is the busiest, and every day it is necessary to respectfully guard the heavens, the Taoist priests on earth. When the mage casts the spell, he always calls out to the heavens, "Where is the Gong Cao on duty?" You have to be on call, and you can't help but be tired, so the duty day Gong Cao is also called the duty Gong Cao.
In the thirty-ninth episode of the Golden Plum Bottle, the Daoist official beat Ximen Qing at the Jade Emperor Temple and set up many rune seals, one of which was to ask Gong Cao to act as a rune sender, "playing the three-day gate to transport Guan Wen". He wrote for the sixty-sixth time: "The golden boy raises smoke, the jade girl scatters flowers, and holds the festival." The altar god general, the three realms of the rune, the four straight (value) Gong Cao, the city god society order, the land only to welcome, all of them are complete. "That is, the god position enshrined on the altar of The True Man when Huang Zhenren was practicing." For example, in the thirteenth time of Dream of the Red Chamber, the monk Dao wrote on the list of Qin Keqing's excesses: I respectfully invite all the gods such as Galan, Jiezhen, Gongcao, etc., the holy grace and, and the gods Weiyuan Town... It can be seen that the Four Values Gong Cao also presented the expression of "Shangda Heavenly Court" (after burning) to the human world, and served as a scrivener.
Looking at the above, although the Four Values Gong Cao was a small official, he had great responsibilities, so he was valued by the Heavenly Court and embraced by Taoism.