It means: it can reveal the way of a saint and express the system of the dynasty. The main object described here is calligraphy.
The words come from Kang Youwei's "Xumu" in "Guangyi Zhou Shuangji": "It can be used to understand the holy way, to develop the king's system, to understand people's principles, and to change things. Then carve one and end art. Small skills and the great road of the world carve out their essence, and the shape of Mingsui is the same."