Zen Buddhism

Portrait of Honen by Fujiwara Takanobu from the twelfth century:

DelanceyPlace.com has a selection from Japan: A Short History by Mikiso Hane:

Buddhism, which arose in roughly the sixth century, found its way to Japan from China no later than the sixth century, but perhaps as early as the third century. However, it began to gain greater popularity during the tumultuous Heian period (794 to 1185), an era which brought a sense of despair that may have led people to seek spiritual comfort. The particular form of Buddhism know as Zen or (Chan) gained a following in Japan at this same time, especially among the samurai warriors who had to face life and death on the battlefield.
In theory, the code of the warrior called on the samurai to be chivalrous and protect the weak, the helpless, and the defeated but, in reality, the samurai was trained to kill, so they usually behaved as ruthless killers. It was not until the Tokugawa era when firm control was established by the Tokugawa shogunate, and there were no violent conflicts, that the code of the warriors on chivalrous, honorable behavior came to be spelled out.
While Buddhism gained popularity among the upper class during the Heian period, it spread more rapidly among the common people in the Kamakura period (1185-1333) and after. This development may have been the result of the chaos, conflict, and power struggles that developed in the later part of the twelfth century and prevailed into the sixteenth century. People were also beset by natural calamities periodically. Thus the 'end of the world', as envisaged in Buddhist thinking, may have appeared to be near at hand. This sense of despair and pessimism may have led people to seek spiritual comfort in the emerging Buddhist sects that reached out to the common people. The Mahayana branch of Buddhism which flourished in China, Korea, and Japan envisioned the rebirth into the Land of Bliss. In the Heian period, emphasis was placed on rituals and recitation of spells and magical formulae. The more often the mantras were repeated the better the chances of salvation. One person, it is said, set aside one bean for every mantra he cited, and accumulated 3.6 billion beans.
In Mahayana Buddhism people were taught that salvation was to be achieved by faith in the merciful Buddhas and Bodhisattvas (those who have achieved enlightenment but remain on earth to help others gain salvation). Amida Buddha, the Body of Bliss, became the most popular Buddha in Japan. Rather than comprehension of Buddhist doctrines and recitation of mantras, the Buddhist leaders who emerged in the Kamakura period emphasized devotion to Amida Buddha and other merciful Buddhas for salvation. These new leaders founded their own sects.
Among the Kamakura Buddhist leaders was Honen (1133-1212) (painting, above) who founded the Pure Land (Jodo) Sect; he taught that all that was needed to gain salvation was reliance on the saving power of Amida Buddha. Honen's disciple Shinran (1173-1262) made salvation even easier by insisting that all that was necessary was one sincere invocation of Amida's name. This contrasted with Honen, who taught that the more often Amida's name was invoked, the better the chances of salvation. Shinran also taught that moral conduct was irrelevant to salvation. Everybody, good or evil, would be saved if they relied wholly on Amida Buddha. In fact, an evil person who realized that he could not save himself might have a better chance of salvation than the good person who felt his good conduct ensured him salvation. By giving oneself over completely to Amida Buddha, Shinran taught that one would become a moral person. He called his sect the True Pure Land Sect (Jodo Shinshu) and it won a wide following among the downtrodden. Since external conduct was not relevant to salvation, Shinran contended that adherence to injunctions against the consumption of certain food and drink, such as beef and alcohol, was not necessary for salvation. He also believed that the clergy need not lead a life different from the laity, and rejected monasticism and clerical celibacy. He set out to reach the common people and went to outlying, impoverished regions to spread his message to aid the downtrodden people, and gained a wide following among the peasantry. Thus the True Pure Land Sect gained a popular following and retained the faith of the masses to the present day.
The other sect that gained a popular following was the Nichiren (Lotus) Sect, founded by Nichiren (1222-82). He held that the three bodies of Buddha emphasized in the Lotus Surra, that is, the Body of Essence, the Body of Bliss (Amida Buddha) and the historical Buddha are a unity and equal in importance. Recitation of the Lotus Surra would enable one to gain salvation. He condemned the other sects as propagating false teachings and set out to replace them with his doctrine. His dogmatism and intolerance set him apart from the other sects, which tended to be more tolerant of diverse beliefs. Nichiren also tended to be nationalistic, and his thinking was akin to Shinto nationalism. Beside helping people to gain salvation he set out to be 'the Pillar of Japan, the Great Vessel of Japan'. He stressed service to the country and obligation to the sovereign. Japan, he asserted, was the land of the gods destined to be the universal center of the Nichiren Sect. His militant viewpoint won over many samurai, but his sect also won a wide following among the masses and has remained a vibrant sect.
Zen Buddhism also emerged as a significant movement in this period. It tended to influence the cultural sphere of Japan more than the other sects. As Chan Buddhism, it was introduced to China from India in the sixth century or earlier. It entered Japan in the Heian period, but did not become an influential sect until the Kamakura period, when its teachings appealed to the samurai class. Unlike the other sects, Zen does not preach salvation through faith in the Buddhas or Bodhisattvas. By means of meditation and concentration 'enlightenment' (satori), becoming one with the underlying reality unencumbered by surface illusions, will be achieved. Reason, knowledge, scriptures, and mantras will not aid in achieving satori. One has to probe directly into one's soul to grasp reality and one's Buddha nature. Once one achieves satori one cannot transmit this reality to others by words. Bodhidharma, who brought Chan Buddhism to China said: 'A special transmission outside the scriptures; no dependence upon words and letters; direct pointing at the soul of man; Seeing into one's nature and the attainment of Buddhahood.'
Two Zen sects emerged, emphasizing different approaches to achieve satori. One stressed zazen, sitting in meditation. The other emphasized koan, the enigmatic, paradoxical themes, to break one's habit of relying on reason to liberate the unconscious, for example: 'What is the sound of one hand clapping.'
Because Zen required discipline and concentration, it did not gain a mass following among the populace. But it won a strong following among the samurai, who had to face life and death on the battlefield. A sixteenth-century warlord told his followers to devote themselves to Zen: 'Zen has no secrets other than seriously thinking about life and death.' Many samurai and modern warriors entered Zen monasteries to discipline themselves and rise above the fear of death. Zen emphasis on grasping the essence of the nature of things had a significant impact on cultural developments.

Rico says that Buddhism, especially the Zen variant, is the only religion he can buy into... (But Rico always asked a different question: 'How much clap can you get with one hand?"