At Buddhist temples, gongs called “geumgo” (金鼓) are traditionally used to signal rituals, gatherings, and mealtimes. Interestingly, “geumgo” were originally gongs and drums used on the battlefield for signaling during warfare, as documented in historical texts such as Records of the Grand Historian (史記), The Art of War (孫子兵法), and Comprehensive Mirror to Aid in Government (資治通鑑).

Geumgo are believed to have been used as Buddhist ritual implements since at least the eighth century. This supposition is based on a passage from The Sutra of the Golden Light (金光明最勝王經), which was translated into Chinese by Monk Yijing (義淨, 635–713) of the Tang Dynasty in the year 703. A geumgo is mentioned in volume 3 of the sutra, entitled “The Chapter on the Dream of a Gong and Repentance” (夢見金鼓懺悔品):

“After personally hearing the wonderful Dharma from the Buddha, Ruciraketu Bodhisattva returned to his original place with great joy and his mind focused on a single thought. That night in his dream, he saw a large geumgo that shone as brilliantly as the sun. Within its light, he saw countless Buddhas from the ten directions of the world, surrounded by unending crowds of people and sitting beneath precious trees on platforms made of crystal, expounding on the Dharma. He saw a brahman holding a stick and loudly beating the geumgo, and within the sound, he chanted the subtle gāthā (verses of scripture) and clarified the method of repentance.”
(爾時妙幢菩薩. 親於佛前. 聞妙法已. 歡喜踊躍. 一心思惟還至本處. 於夜夢中. 見大金鼓. 光明晃耀. 猶如日輪. 於此光中. 得見十方無量諸佛. 於寶樹下坐琉璃座. 無量百千大眾圍繞而為說法. 見一婆羅門. 桴擊金鼓. 出大音聲. 聲中演說微妙伽他明懺悔法.)

Thus, it is presumed that geumgo were being used as Buddhist ritual implements by the time this sutra was written. Another pertinent record can be found in the “Seogeumdang Hall Section” (西金堂條) of the “Treasure Inventory” (寶字記) in Kofukuji Temple Asset Ledger (興福寺資財帳), which was written between 757 and 760 at Kofukuji Temple in Nara, Japan. One of the listed treasures is a percussion instrument called a “kagenkei” (華原磬), which had been introduced from the Tang Dynasty, and is described as follows:

“The geumgo is held on a stand that is 3 cheok, 5 chi, 5 pun (appx. 108 cm) tall, with a diameter of 7 chi and 8 pun (appx. 24 cm). It is 2 cheok, 3 chi, and 9 pun long (appx. 73 cm), and 2 cheok, 3 chi, and 7 pun wide (appx. 72 cm). A Brahman stands on the left, holding a mallet...” (金鼓一具 高拜臺三尺五寸五分 鼓徑七寸八分 長二尺三寸九分 廣二尺三寸七分 左婆羅門形一人 持槌…)

From this record, we can understand that a “kagenkei” was a gong that was struck by a brahman with a mallet. The record also matches the description of a “geumgo” from The Sutra of the Golden Light, indicating that a kagenkei and geumgo were the same type of instrument.

At present, there are no known records explaining how the geumgo was introduced to Korea. But in the section entitled “50,000 True Bodies of Mt. Tai” (臺山五萬眞身) in “Volume 3: Pagodas and Statues” (㙮像) of Memorabilia of the Three Kingdoms (三國遺事), it states that one of the thirty-six transformations of Manjusri Bodhisattva is a geumgo. Significantly, this section includes a date: the first year of “Shenlong” (神龍), an era name from the Tang Dynasty that corresponds to 705 in the Roman calendar. This suggests that geumgo were being produced Korea by the early eighth century. Another record from Donghwasa Temple in Palgongsan Mountain reports that a geumgo was produced in 842.

However, the oldest surviving geumgo in Korea is this one, which bears an inscription that reads “sixth year of Xiantong (咸通) reign,” another Tang era name, which corresponds to 865. As the oldest Buddhist gong of its kind, it has rightly been designated as a Treasure (formerly Treasure #1907).

Although records suggest that geumgo were produced in Korea by the early eighth century, none from that era have survived. Hence, this gong can be considered the progenitor of Korean Buddhist gongs. The front of the gong, where the sound was produced, is divided into three sections by raised concentric circles: the striking area in the center, the inner section, and the outer section. The back of the gong is open, forming a large resonance chamber. The side of the gong is divided by a raised ridge that runs around the entire circumference, with three pentagonal knobs attached on the top and two sides (respectively) at ninety-degree intervals. The inscription is embossed on the side.

One of the most intriguing details about this gong is the lack of designs on the front striking surface. Most Korean Buddhist gongs feature a lotus design in the striking area and a cloud design on the outer area. However, it seems that early examples of geumgo did not include such designs. Supporting this hypothesis, another gong with no designs on the striking area, which is estimated to date from the tenth century, was discovered in 2009 at the site of Ingaksa Temple in Gunwi. Based on these two gongs, it is believed that Unified Silla gongs from the mid-ninth century to the tenth century were not decorated on the striking area.

The inscription on the side of the gong is embossed in reverse script, reading from left to right, as if seen in a mirror:

“咸通陸歲乙酉二月十二日成內月(?)供寺禁口”

According to the inscription, the gong was made on the twelfth day of the second month of the sixth year of the Xiantong reign, which corresponds to 865. Notably, the inscription calls the gong a “geumgu” (禁口), rather than “geumgo,” suggesting that the name of these gongs may have slightly changed over time. Unfortunately, part of the inscription is damaged, so that the name of the temple where this gong was dedicated is now illegible. The part of the inscription reading “成內月(?)供寺” may pertain to the name of the temple, but could also be the time when the gong was offered to the temple. Notably, the character that follows “內” is “月,” which can mean either “month” or “moon,” but is also a radical. Thus, the name of the temple probably cannot be definitively confirmed.

In summary, this gong with the inscription “sixth year of the Xiantong reign” is the oldest extant Buddhist gong in Korea. Unlike most gongs from the Goryeo period or thereafter, it does not feature designs of lotus flowers or clouds on the front. This undecorated style seems to have been maintained until at least the tenth century, as evidenced by the gong discovered at the site of Ingaksa Temple. Despite its lack of designs, this gong is still an invaluable artifact that helped to lay the foundation for the long and distinguished tradition of Korean Buddhist gongs.