Pine trees hold a unique place among flora, revered for their resilience to severe cold, evergreen nature, and timeless endurance without seasonal color changes. These qualities have inspired countless scholars and artists, who use the pine as a metaphor for noble aspirations. Among plants, the pine tree was among the first to be represented in painting and literature.

In Records of the Grand Historian (Shiji), the pine, chrysanthemum, and plum blossom are collectively referred to as the "Three Friends of Winter," with the pine earning the title "Leader of All Trees." The association of pines with virtue dates back to ancient times, as early as the pre-Qin period, where it was imbued with clear moral symbolism. Confucius, in The Analects, remarked, "Only in the harshness of winter does one realize that the pine and cypress do not wither." His poetic praise highlighted the pine's steadfast character, serving as a moral lesson for his disciples and embedding a connection to human virtue and self-cultivation.

With the emergence of Confucianism, Buddhism, and Daoism, the cultural significance of pine trees deepened, representing sublime beauty, steadfastness against frost and snow, enduring vitality, and diverse forms of aesthetic expression. During the Han and Wei dynasties, before the rise of landscape and bird-and-flower painting, figure painting was heavily influenced by Confucian thought. Emphasis was placed on capturing the style and demeanor of individuals, aligning the depiction of their figures with the surrounding environment to achieve spiritual resonance. This concept of "conveying spirit through form" made the pine tree, imbued with Confucian ideals, a key element in framing human characters. Over time, the pine became a standard cultural symbol in Chinese painting, embodying the unique cosmological and aesthetic perspectives of the Chinese people and serving as one of the most frequently depicted subjects in traditional art.

Chung Chen Sun's Righteousness is a remarkable flower-and-bird painting centered on the pine. The work employs a combination of long and short lines to depict the twists, turns, light, and shadow of the pine trunk. The long lines are interspersed with dry brushwork, eliminating the smooth and immature feel of polished strokes. Through this textured dry-brush technique, a sense of flying white emerges, imparting the ruggedness of the pine. For areas requiring emphasis, light and shadow are brought out with layered strokes. The brushwork exudes the essence of seal and clerical script, appearing robust and rounded. The frequent use of circular brush movements conveys the pine trunk’s aged and majestic character through its contours, with minimal application of ink, showcasing the artist's deep understanding of calligraphic technique. Inscribed centrally on the painting are the words "浩然正气" (Righteousness), metaphorically linking the pine to human virtues and imbuing the work with profound cultural sentiment.