It is recorded that the origin of spring couplets can be dated back to 1,000 years ago when people hung taofu (桃符, written charms on peach wood) on doors.
Legend has it that there was a huge peach tree stretching for more than 1,500 kilometers on a mountain in the ghost world. To the northeast of the tree, two guards named Shentu and Yulei guarded the entrance to the ghost world. They would catch the ghosts who harmed people and then send them to tigers as food.
Therefore, all ghosts were afraid of the two guards. It was believed that hanging a piece of peach wood with an inscription of the two guards’ names on doors could scare evil things away.
By the Song Dynasty (960-1279), people began to write two auspicious antithetical lines on the peach wood instead of the names of the two guards. Later, the peach wood was replaced by red paper, which symbolizes good luck and happiness. Since then, pasting spring couplets has been a custom to welcome the new year and express best wishes.