Nio

Niō (仁王^?) or Kongōrikishi (金剛力士^?) are two wrath-filled and muscular guardians of the Buddha standing today at the entrance of many Buddhist temples in East Asian Buddhism in the form of frightening wrestler-like statues. They are dharmapala manifestations of the bodhisattva Vajrapāṇi, the oldest and most powerful of the Mahayana Buddhist pantheon. According to Japanese tradition, they travelled with Gautama Buddha to protect him and there are references to this in the Pāli Canon as well as the Ambaṭṭha Sutta. Within the generally pacifist tradition of Buddhism, stories of dharmapalas justified the use of physical force to protect cherished values and beliefs against evil. The Niō are also seen as a manifestation of Mahasthamaprapta, the bodhisattva of power that flanks Amitābha in Pure Land Buddhism and as Vajrasattva in Tibetan Buddhism.

Kongōrikishi are usually a pair of figures that stand under a separate temple entrance gate usually called Niōmon (仁王門^?) in Japan, hēnghā èr jiàng (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 Christianity, they signify "everything" or "all creation". The contraction of both is Aum (ॐ), which is Sanskrit for The Absolute.

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Wikipedia