Calligraphy by Ishimuro Zenkyu (Nekōgo / 25th February, 2nd

Sekishitsu Zenkyū's Bokuseki: A Masterpiece of Zen Calligraphy from 1363

Among the treasured calligraphic works preserved in Japan, the bokuseki (Zen calligraphy) by Sekishitsu Zenkyū holds a place of special distinction. Designated as an Important Cultural Property, this particular piece—a nenkōgo (incense-offering verse) dated to the 25th day of the second month of Jōji 2 (1363)—stands as a powerful testament to the spiritual depth and artistic mastery of one of medieval Japan's most accomplished Rinzai Zen monks. Now housed at the Tokyo National Museum as part of the prestigious Tokiwayama Bunko collection, this work invites viewers to encounter the living spirit of Zen Buddhism as expressed through the art of the brush.

Who Was Sekishitsu Zenkyū?

Sekishitsu Zenkyū (1294–1389) was a towering figure in the Rinzai school of Zen Buddhism during the late Kamakura and Nanbokuchō periods. Born in Chikuzen Province (present-day Fukuoka Prefecture), he traveled to Yuan-dynasty China in 1318 at the age of 25, where he studied under several eminent masters. He ultimately became a disciple of Gulin Qingmao (Kurin Seimu) at Baoning Temple in Nanjing, inheriting his dharma lineage.

After eight years of rigorous training in China, Sekishitsu returned to Japan in 1326, accompanying the Chinese monk Seissetsu Shōchō. Upon his return, he rose to prominence within Japan's Zen establishment, serving as head abbot of some of the most prestigious temples in the land, including Tenryūji in Kyoto, Engakuji and Kenchōji in Kamakura. He is also revered as the founder of Heirinji Temple in Musashi Province (present-day Saitama Prefecture) and Kōtokuji in Bingo Province. A master of poetic verse, he contributed significantly to the foundations of Gozan literature—the literary tradition of Japan's Five Mountain Zen monasteries. He passed away in 1389 at the remarkable age of 96.

Understanding the Nenkōgo: Incense-Offering Verse

The specific content of this bokuseki is a nenkōgo—a ceremonial verse composed and recited by a Zen master while offering incense during a Buddhist memorial service. This particular nenkōgo was written by Sekishitsu at the age of 70 when he served as the presiding monk at the 13th memorial anniversary of Getsurin Dōkō (also known as Tsukirin Dōkō), a fellow disciple under their shared master Gulin Qingmao in China. Getsurin is known as the founding abbot of Chōfukuji Temple in Kyoto.

Written in 1363 (Jōji 2, also known as Shōhei 18 in the Southern Court calendar), this work captures a deeply personal moment of spiritual remembrance between dharma brothers—monks who shared the same teacher and the profound experience of Zen training in a foreign land. The nenkōgo genre itself is an important form within Zen literary traditions, combining religious devotion, philosophical expression, and calligraphic artistry into a single powerful act.

Why This Work Is Designated as an Important Cultural Property

This bokuseki has been designated as an Important Cultural Property (Jūyō Bunkazai) by the Japanese government for several compelling reasons. First, it represents one of the finest surviving examples of Sekishitsu Zenkyū's calligraphy, and his representative works are considered among the most significant bokuseki of the Nanbokuchō period. Art historians have noted that Sekishitsu's brushwork bears a resemblance to the later Chinese calligrapher Wang Duo (1592–1652) and exhibits a refined quality rooted in the classical traditions of the Jin and Tang dynasties. His style is described as adding an element of refined elegance to the bold, vigorous manner of his master Gulin Qingmao.

Second, the piece holds tremendous historical value as a document of Zen cultural exchange between China and Japan during the medieval period. It provides insight into the rituals and personal bonds within the Gozan monastic community. Third, the commanding scale and dignified presence of the calligraphy itself—described by scholars as majestic and awe-inspiring—make it a work of outstanding artistic merit. Together with other related works such as a congratulatory text composed for an imperial calligraphic plaque bestowed by Emperor Go-Kōgon, these pieces constitute the pinnacle of Sekishitsu's calligraphic legacy.

Highlights and What to Look For

When viewing this bokuseki, visitors should pay attention to several notable features. The brushwork displays a remarkable confidence and dynamism characteristic of a mature Zen master at the height of his powers. Each stroke conveys both the spiritual authority of the writer and the depth of feeling behind the memorial occasion. The ink on paper format (shihon bokusho) measures approximately 47.0 × 99.5 centimeters, allowing the viewer to appreciate the expressive variation in ink density, brush speed, and pressure that makes Zen calligraphy such a visceral art form.

Compared to secular calligraphy, Zen bokuseki is distinguished by its directness, intensity, and sense of spontaneous energy. Sekishitsu's work exemplifies these qualities while adding his own distinctive refinement. The viewer can appreciate how the calligrapher balances powerful, bold strokes with moments of delicate control, creating a visual rhythm that mirrors the cadence of Zen thought. For those familiar with the tea ceremony tradition, bokuseki of this caliber has long been treasured as the supreme hanging scroll for the tokonoma (alcove) of the tea room—a practice that reflects the deep connection between Zen aesthetics and Japanese tea culture.

The Tokiwayama Bunko Collection

This bokuseki belongs to the Tokiwayama Bunko, one of Japan's most distinguished private art collections. Founded in 1943 by the industrialist Sugawara Tsūsai (1894–1981), the collection centers on four main pillars: Zen calligraphy (bokuseki), Chinese and Japanese paintings, Chinese ceramics, and Tenjin (Sugawara no Michizane) iconography. The collection includes 2 National Treasures, 21 Important Cultural Properties, and 18 Important Art Objects.

Originally housed in Sugawara's residence on Kamakura-yama, the collection was publicly displayed there until fire safety regulations necessitated its closure. Today, the Tokiwayama Bunko's works are entrusted to the Tokyo National Museum, the Kyushu National Museum, and the Keio University Museum Commons, where they continue to be exhibited and studied. For visitors interested in Zen calligraphy, the Tokiwayama Bunko collection represents one of the finest assemblages in the world.

Visiting the Tokyo National Museum

The Sekishitsu Zenkyū bokuseki is held at the Tokyo National Museum (Tōkyō Kokuritsu Hakubutsukan), located in the scenic surroundings of Ueno Park. As Japan's oldest and largest national museum, founded in 1872, it houses approximately 120,000 cultural properties, including 89 National Treasures and over 640 Important Cultural Properties. The museum's permanent collection galleries regularly rotate works, so calligraphy and bokuseki pieces are displayed on a scheduled basis to preserve their condition.

Visitors planning to see this specific work should check the museum's exhibition schedule in advance, as delicate paper-based artworks are only displayed for limited periods. When on view, the bokuseki is typically exhibited in the Honkan (Japanese Gallery), which features thematic rooms dedicated to different periods and art forms of Japanese cultural history. Audio guides and English-language signage are available throughout the museum to enhance the experience for international visitors.

Surrounding Attractions in Ueno

The Tokyo National Museum is situated within Ueno Park, one of Tokyo's most culturally rich districts. Within walking distance, visitors can explore a wealth of world-class institutions and scenic spots. The National Museum of Western Art, designed by Le Corbusier and itself a UNESCO World Heritage Site, is just steps away. Nearby, the National Museum of Nature and Science offers fascinating exhibits on natural history, while the Tokyo Metropolitan Art Museum and the Ueno Royal Museum host rotating exhibitions of contemporary and classical art.

Ueno Park itself is famous for its cherry blossoms in spring and is home to Shinobazu Pond, where visitors can enjoy boat rides surrounded by lotus flowers in summer. The historic Ueno Tōshōgū Shrine, dedicated to Tokugawa Ieyasu, is another notable destination within the park. For those seeking a more immersive cultural experience, the traditional neighborhood of Yanaka, with its old-world atmosphere and charming shops, lies just north of the park.