Kongōrikishi (金剛力士) or Niō (仁王) are two wrath-filled and muscular guardians of the Buddha, standing today at the entrance of many Buddhist temples all across Asia including China, Japan and Korea in the form of frightening wrestler-like statues. They are manifestations of the Bodhisattva Vajrapāṇi protector deity and the oldest and most powerful of the Mahayana pantheon. According to Japanese tradition, they travelled with the historical Buddha to protect him and there are references to this in the Theravada Scriptures as well including the Ambatta Sutta. Within the generally pacifist tradition of Buddhism, stories of Niō guardians like Kongōrikishi justified the use of physical force to protect cherished values and beliefs against evil. Nio-Vajrapani is also seen as a manifestation of Mahasthamaprapta or the Bodhisattva of Power that flanks Amida in the Pure Land Tradition and as Vajrasattva, the Dharmapala of the Tibetan tradition.
Kongōrikishi are usually a pair of figures that stand under a separate temple entrance gate usually called Niōmon (仁王門) in Japan, Heng Ha Er Jiang (哼哈二将) in China and Geumgangmun (金剛門) in Korea. The right statue is called Misshaku Kongō (密迹金剛) and has his mouth open, representing the vocalization of the first grapheme of Sanskrit Devanāgarī (अ) which is pronounced "a". The left statue is called Naraen Kongō (那羅延金剛) and has his mouth closed, representing the vocalization of the last grapheme of Devanāgarī (ह [ɦ]) which is pronounced "ɦūṃ" (हूँ). These two characters together symbolize the birth and death of all things. (Men are supposedly born speaking the "a" sound with mouths open and die speaking an "ɦūṃ" and mouths closed.) Similar to Alpha and Omega in [[Wikipedia:Christianity|Christianity]], they signify "everything" or "all creation". The contraction of both is Aum (ॐ), which is Sanskrit for The Absolute.
Misshaku Kongō or Agyō
Misshaku Kongō (密迹金剛), also called Agyō (阿形?, "a"-form, general term open-mouthed statues in aum pair), is a symbol of overt violence: he wields a vajra mallet "vajra-pāṇi" (a diamond club, thunderbolt stick, or sun symbol) and bares his teeth. His mouth is depicted as being in the shape necessary to form the "ah" sound, leading to his alternate name, "Agyō". Misshaku Kongō (密迹金剛) is Miljeok geumgang in Korean, Mìjī jīngāng in Mandarin Chinese, and Mật tích kim cương in Vietnamese. It is equivalent to Guhyapāda vajra in Sanskrit.
Naraen Kongō or Ungyō
Naraen Kongō (那羅延金剛), also called Ungyō (吽形?, "um"-form, general term open-mouthed statues in aum pair) in Japanese, is depicted either bare-handed or wielding a sword. He symbolizes latent strength, holding his mouth tightly shut. His mouth is rendered to form the sound "hūṃ" or "Un", leading to his alternate name "Ungyō". Naraen Kongō (那羅延金剛) is Narayeon geumgang in Korean, Nàluóyán jīngāng in Mandarin Chinese, and Na la diên kim cương in Vietnamese.
A manifestation of Kongōrikishi that combines the Naraen and Misshaku Kongōs into one figure is the Shukongōshin at Tōdai-ji in Nara, Japan. Shukongōshin (執金剛神), literally "vajra-wielding spirit", is Shūkongōshin or Shikkongōjin in Japanese, Jip geumgang sin in Korean, Zhí jīngāng shén in Mandarin Chinese, and Chấp kim cang thần in Vietnamese.
Kongōrikishi are an interesting case of the possible transmission of the image of the Greek hero Heracles to East Asia along [[The_Silk_Road|the Silk Road]]. Heracles was used in Greco-Buddhist art to represent Vajrapani, the protector of the Buddha (See also Image), and his representation was then used in China and Japan to depict the protector gods of Buddhist temples. This transmission is part of the wider Greco-Buddhist syncretic phenomenon, where Buddhism interacted with the Hellenistic culture of [[Wikipedia:Central Asia|Central Asia]] from the 4th century BC to the 4th century AD.
Nio Zen Buddhism was a practice advocated by the Zen monk Suzuki Shōsan (1579-1655), who advocated Nio Zen Buddhism over Nyorai Zen Buddhism. He recommended that practitioners should meditate on Nio and even adopt their fierce expressions and martial stances in order to cultivate power, strength and courage when dealing with adversity. Suzuki described Nio as follows: “The Niõ (Vajrapani) is a menacing God. He wields the kongõsho (vajra) and he can crush your enemies. Depend on him, pray to him that he will protect you as he protects the Buddha. He vibrates with energy and spiritual power which you can absorb from him in times of need.”
The Kiddy Grade characters Un-ou and A-ou are named for Ungyō and Agyō, respectively.
The Street Fighter characters Akuma and Gouken are based around Nio.
In chapter 74, Yotsuba takes picture of a man on the street whom she mistakes for a Nio.