Kūkai expected twenty years of study in China and mastered it in months
In 804 a little-known Japanese monk sailed for Tang China hoping someone could explain a baffling Sanskrit scripture. Within months of meeting the master Huiguo he received the highest esoteric initiation. Kūkai came home to found Shingon Buddhism, and legend even credits him with inventing the kana script Japanese still uses.
He was born Saeki no Mao in 774 within the grounds of Zentsū-ji temple on Shikoku, into an aristocratic branch of the old Ōtomo clan. At fifteen his maternal uncle began teaching him the Chinese classics, and by 791 he was studying at the government university in Nara, the usual path into officialdom. The family's standing, though, had slipped after its clan chief was accused of arranging a rival's assassination.
Kūkai turned instead to wandering asceticism, retreating to remote mountains to chant the mantra of the bodhisattva Kokūzō, living partly outside a state system that tightly licensed monks. At 24 he produced his first major work, Sangō Shiiki, drawing on Confucian, Daoist and Buddhist classics. A dream pointed him to the Mahavairocana Tantra, but much of his copy was untranslated Sanskrit in Siddhaṃ script and the rest was obscure. Nobody in Japan could explain it.
So he joined the official embassy of 804. Of its four ships, one turned back in a storm and another vanished; his own reached Fujian weeks late and was impounded until Kūkai wrote to the provincial governor in fluent Chinese. In Chang'an he studied Sanskrit with the Gandharan teacher Prajñā, and in 805 met Huiguo at Qinglong Monastery, who greeted him as if expected and quickly passed on the complete esoteric lineage. Kūkai returned in 806 as its eighth patriarch, trained in calligraphy and poetry as well.
Home politics were less welcoming. A new emperor cared little for Buddhism, and the rival monk Saichō, founder of Tendai, had the court's ear. Kūkai later granted Saichō two levels of initiation but withheld the final one. By 810 he headed Tōdai-ji in Nara, and public initiations at Takao-san in 812 confirmed him as Japan's leading esoteric master. Revered after his death in 835 as Kōbō Daishi, he is also linked by legend to the Iroha poem that helped standardise kana.
Source: Kūkai
