Those who study the law trace back to its source, and those who study the law also inherit its flow.

Hello! I'm happy to answer your question:

Pi's History of Confucian Classics said: "Before the Han Dynasty, it was more important to learn the law. After the Han Dynasty, it was more important to learn the law, and then it became a family statement. Those who study the law, trace their source, and those who study the law, get their flow. " That is to say, in the Western Han Dynasty, once a master was honored as a doctor by the court, like Dong Zhongshu, the classics he taught could become a model, and then his disciples could be more detailed and develop into a small faction. This is called family law, such as Yan's Ram and Yan's Ram. China's calligraphy education first followed this method.

To sum up, the meaning of the sentence you asked is: If Dong Zhongshu is in that position, the classics he teaches can become models, and then his disciples can be more detailed and develop into small factions.

If you are satisfied with my answer, please adopt it. Thank you!