The Buddhist sects that developed in Japan during the Kamakura period (1185-1336)–notably the Jōdo sect, the Zen sects, and the Nichiren sect–are characteristically Japanese. They manifest a lofty purity and a penetration into the true spirit of Buddhism that are difficult to find elsewhere in the history of the religion. In these sects, simple acts like chanting formulas in praise of Amida Buddha or the Lotus Sutra or like seated meditation are considered sufficient for salvation in themselves without philosophizing or theoretical inquiries. But this does not mean that these sects lack theoretical foundations. Quite to the contrary, their founders evolved direct and clear acts of practical faith–chanting and meditation–after profound and extensive scholarly research. The ordinary man is not required to perform such research for himself: he need only follow the directions of his religious leader. Indeed, in these sects, theoretical study and speculation are forbidden as hindrances to practical faith. (Page 159-160)

See this blog post.