Strongly penetrating the back of the paper and penetrating into the wood were first used to describe calligraphy.
Strong enough to see through the back of the paper: Describing the calligraphy as strong and powerful, the strokes of the pen almost penetrate to the back of the paper. It is also often used to describe poems and other works that are clever and profound in connotation. From Zhao Yi's "Oubei Poetry Talk" of the Qing Dynasty, "(Lu You's poems) the meaning comes first in the pen; the power penetrates the back of the paper." It means that the poem has a profound intention and concise words.
Three points into the wood: describes the strength and power of calligraphy, and also means a deep and thorough insight into an article or thing. From Zhang Huaiguan's "Shujuan·Wang Xizhi" of the Tang Dynasty, "When the Jin Dynasty offered sacrifices to the northern suburbs, he also prayed for the edition. The workers cut it and the pen penetrated the wood into three parts."
Extended information:
" Synonyms of "penetrating through the back of the paper": a pen as big as a rafter, a powerful pen; antonyms: understatement.
Understatement: originally refers to using light colors to paint lightly when describing. Nowadays, it mostly refers to talking and writing articles that lightly brush over important issues without paying attention to them. It also means doing things effortlessly. From Chapter 8 of Wenkang's "Heroes of Sons and Daughters" of the Qing Dynasty: "This Toutuo is extremely ferocious. How could you, girl, kill him so easily?" ;Antonym: glimpse.
Have a glimpse: Refers to a metaphor for roughly seeing something. From "Shishuo Xinyu·Fangzheng" by Liu Yiqing of the Southern Dynasty and Song Dynasty.
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