What's the use of "Jiang Taigong is here"?

Jiang Taigong is one of the customs in the Han nationality where everything is forgiven. On New Year's Eve, the Kitchen God and couplets should be posted to take him home and keep him safe for one year. It is also necessary to paste the door gods, Spring Festival couplets, the word "fu" and red money to exorcise evil spirits and receive blessings. In the old society, the Han people even posted "Jiang Taigong is here, and everything is free". This kind of bar is attached to the lintel, which is rare on the gate. Most of them are pasted on the lintels of screen doors, living rooms and halls, or on beams and floors. Shopkeepers like to stick it on the shop floor or above the entrance and exit, which is very eye-catching. This custom was very popular in the past and has a long history. This custom is often seen in some rural houses or some large-scale activities.