Who is the "two-door god" in China's mythology?

The mythical door gods are Shen Tu and Lei Yu.

Door-keeper, that is, the guard of Simen, is a painting posted on the door during the Lunar New Year. As guardians of folk beliefs, people stick idols on doors to drive away evil spirits and ghosts, defend their homes, maintain peace, help public utilities and bring good luck. It is the beloved patron saint of China people. According to traditional customs, every household is busy writing couplets and door gods on the eve of the Spring Festival to pray for the coming year.

According to historical records, the activity of "worshipping the door" appeared in the Zhou Dynasty, which was an extremely important ceremony. Among the legends of door gods, the legends of Shen Tu and Lei Yu have been circulated among the people for a long time, and they are recorded in ancient books such as Shan Hai Jing, General Meaning of Customs, Rebuilding the Integration of Weft Books, and Searching for Gods by Three Religions.

There is such a description in Shan Hai Jing: "There is a big peach tree on Dushuo Mountain in the East China Sea, which bends for three thousand miles. Its ugly branches are named Ghost Gate in the northeast, and ghosts come and go. One is Ershen, the other is Shen Tu, and the other is Lei Yu. Master reading, attracting ghost victims. " It is said that there is a sacred mountain "Dushuo Mountain" in the East China Sea, and there is a particularly large peach tree on this Dushuo Mountain. This big peach tree winds for three thousand miles. In the northeast direction of its branches, there is a "ghost gate", which is the gateway for ghosts to enter and leave. Two gods guarding the gate of hell, one named Shen Tu and the other named Lei Yu, prevent harmful ghosts from entering people's homes.

References:

Baidu encyclopedia, gatekeeper (gatekeeper in folk belief)