What the "Liu Zhong Envoy's Post" reflects is the rebellion of Tian Chengsi, one of the three towns in Hebei (also known as the Three Towns of Heshuo).
The three towns of Hebei refer to the three vassal towns of Lulong, Chengde and Weibo that appeared in Hebei in the late Tang Dynasty. After the Anshi Rebellion ended. In order to win over Shi Chaoyi's Hebei generals, the Tang Dynasty successively appointed Zhang Zhongzhi as the military governor of Chengde Army and gave him the name Li Baochen; Tian Chengsi was appointed as the governor of Wei (now Hebei Damingbei), Bo, De, Cang, and Yingzhou (now southeast of Hebei). He was the defense envoy of the Ministry of Defense and the northern part of Shandong Province. In June 763, he was changed to Wei Bo Jiedushi and was stationed in Weizhou; Li Huaixian was appointed as Lulong Jiedushi of Youzhou. Qian Mu discussed: "After the rebellions of An and Shi in the Tang Dynasty, warriors and warriors marched in formations based on their merits and became each other's lords and kings, except for Jiedu envoys. From this Fangzhen looked at each other in the interior, the larger one connected the state with more than ten states, and the smaller ones It is still combined with three and four. From outside the country, almost all the forces in Fangzhen are. "These are the so-called "Three Towns of Hebei". They all have strong soldiers and have their own officials (each state and county has its own town generals and consuls). Governor, county magistrate). No tribute, marriage, connection." After Tian Chengsi surrendered to the Tang Dynasty in 763, he nominally submitted to the imperial court, but did not obey the central government and formed a local separatist force. In the first month of 775 (the tenth year of the Dali calendar), Tian Chengsi took advantage of the rebellion by the generals in Zhaoyi Town and sent troops to capture Xiangzhou. After the war broke out, Emperor Daizong of the Tang Dynasty ordered Tian Chengsi and others to "keep their territory" and not cross the Leichi. However, Tian Chengsi refused to obey the edict and still sent generals Lu Ziqi to attack Yanzhou and Yang Guangchao to attack Weizhou. In April 775, Emperor Daizong of the Tang Dynasty issued an edict to attack Tian Chengsi. When Qiu Zhenqing analyzed Yan Zhenqing's "Liu Zhong's Letters", "Manuscripts for Nephew Commemoration" and Su Shi's "Huangzhou Cold Food Poems", he elaborated on the subject matter and artistic conception of the work: "The work must have artistic conception, starting from the author's destiny and mental state. , to the integration of various factors that constitute a work, is an indispensable prerequisite. Line is the only formal means of calligraphy art, and words are the subject matter (the first meaning of the subject matter) of calligraphy works. Both can depict a scene. '. For a calligraphy work, in addition to the 'landscape' of lines directly appealing to people's senses, as people identify the words, the 'landscape' of words will always emerge in their minds intentionally or unintentionally, superimposed on the 'landscape' of lines. 'On. Only when these two 'realms' are harmonized first can we talk about the integration of 'meaning' and 'realm': the unity of the author's subjective world and the 'realm' of lines and the 'realm' of words."
Calligraphy is an art of line. The subject matter - the realm depicted by words, although it is in a secondary and subordinate position, but because of its tacit understanding with the author's emotion and the form of the work, it becomes an indispensable prerequisite for forming the artistic conception. The subject matter - As a medium that connects the author's subjective world and form, words have a significance that cannot be ignored in the art of calligraphy. For example, "Huangzhou Cold Food Poetry Post", "Nephew Memorial Manuscript", and "Liu Zhong Envoy Post", the subject matter and diction are all closely related to the emotions expressed in the works. These touching works reflect the harmony of the author's subjective world, subject matter, diction, and form.