Kukai, and the Esoteric Buddhism of Japan

Shingon ("True Word," a rendering of mantra) is the great school of esoteric or tantric Buddhism in Japan, founded by Kukai (774-835), posthumously Kobo Daishi, one of the most influential figures in Japanese religious and cultural history. Having received the esoteric transmission in China, Kukai established his monastic centre on Mount Koya, still the heart of the school.

Shingon teaches that buddhahood is attainable "in this very body" through the practice of the three mysteries, the ritual gestures (mudra) of the body, the sacred formulas (mantra) of speech, and the meditative visualization (using mandala) of the mind, by which the practitioner aligns with and realizes the cosmic Buddha Mahavairocana, of whom all reality is the expression. Its dense symbolic system, its twin mandalas, and its elaborate ritual gave Shingon a lasting influence on Japanese art and on the wider fusion of Buddhas and kami (honji suijaku) that shaped Japanese religion for a millennium.