Assist the emperor to become a wise monarch like Yao and Shun, making the government harmonious and the customs honest.
According to the search on Baidu Encyclopedia, it is known that "to the kings of Yao and Shun, and to make the customs pure" was written in the poem "Twenty-two Rhymes of Presenting Wei Zuocheng" by Du Fu of the Tang Dynasty. "Twenty-Two Rhymes for Wei Zuocheng" is a poem by Du Fu, a great poet of the Tang Dynasty. This poem narrates the author's own talent and learning, as well as his life aspirations and ambitions, confides his frustration in official career and difficult life, and criticizes the dark social and political reality at that time. The whole poem expresses his heart directly and makes an impassioned statement. It is an important poem in which Du Fu recounts his life. To the emperors Yao and Shun, and to make the customs pure means to assist the emperor to become a wise monarch like Yao and Shun, to make the government harmonious and the customs to be honest.
Some of the verses are as follows: He claims to be quite forward, and he immediately ascends to the important road. To the kings Yao and Shun, and to make customs pure. This meaning is actually depressed, and the singing is not hidden.