In order to study and propagate the dharma of Buddhism, it is indispensable to know the difference between Mahāyāna and Hinayāna teachings, provisional and true teachings, and exoteric and esoteric teachings among the various sūtras. In addition, it is also necessary to know the proper time for propagating the teaching, and the capacity for learning of those who are to receive the teaching. Nevertheless, most people in Japan automatically recite the Amitābha Sūtra, chanting “Namu Amida-butsu” devoutly, but thinking little of the Lotus Sūtra.

Many, who are respected for being wise, seem to think that they know the proper time for propagation and the capacity of the people, but actually they believe in the insignificant rather than the significant, believing in the provisional sūtras, while casting aside the true sūtras. Just as the insignificant may become a great evil, a medicine changes to poison, and close relatives become sworn enemies, it is impossible to save such people.

Even those who excel in understanding Buddhism, if they don’t grasp the social conditions of the time, the capacity of the people to receive the teaching, the conditions of the country, and the order of the teachings to be spread, they will not obtain the expected results no matter how hard they work to propagate the teachings. For example, it may be permissible to propagate Mahāyāna teachings in an absolute Hinayāna country, but to propagate Hinayāna teachings in the absolute Mahāyāna country must definitely be avoided. If Hinayāna teachings are forcibly propagated in the country of Mahāyāna Buddhism, disasters will befall the country and the people fall into evil realms.

Shimoyama Goshōsoku, The Shimoyama Letter, Writings of Nichiren Shōnin, Volume 5, Page 66-67