In ancient Chinese mythology, it is said that there is a world of ghosts, in which there is a mountain. On the mountain, there is a big peach tree covering three thousand miles, and there is a golden chicken on the top of the tree. Whenever the golden rooster crows in the morning, the ghosts wandering at night will rush back to the ghost area. The gate of the ghost kingdom is located in the northeast of the peach tree. Beside the gate stood two gods named shenta and Yulei. If the ghost does something harmful at night, Shentu and Yu Lei will immediately find it and catch it, tie it up with a rope made of mang reed and send it to feed the tiger. Therefore, ghosts all over the world are afraid of Shentan and Yulei. So the people carved them with peach wood and put them at their own door to avoid evil and harm. Later, people simply engraved the names of divine tea and Yu Lei on the mahogany board, believing that doing so can also suppress evil and eliminate evil. This kind of peach board was later called “peach talisman”.
In the Song Dynasty, people began to write couplets on mahogany boards. First, they did not lose the significance of mahogany to suppress evil, second, they expressed their good wishes, and third, they decorated the door for beauty. Couplets are also written on red paper symbolizing happiness and auspiciousness and pasted on both sides of doors and windows on the occasion of the Spring Festival to express people’s good wishes for good luck in the coming year.
In order to pray for the well-being of the family, people in some places still keep the habit of sticking door gods. It is said that when two door gods are pasted on the gate, all demons and ghosts will be afraid. Among the people, the door god is a symbol of righteousness and force. The ancients believed that people with strange looks often have magical temperament and extraordinary skills. They are honest and kind-hearted. It is their nature and responsibility to catch ghosts and demons. Zhong Kui, the ghost catching Heavenly Master admired by people, is such a strange appearance. Therefore, the folk door gods are angry, ferocious, holding all kinds of traditional weapons, ready to fight ghosts who dare to come to the door at any time. Because the doors of Chinese folk houses are usually two opposite doors, the door gods are always in pairs. After the Tang Dynasty, in addition to the previous two generals of Shentan and Yulei, Qin Shubao and Yuchi Gong were regarded as door gods.