A diary is an important source of information from which we can learn not only the daily life of the writer, but also the social conditions and historical background of his time. The faith and ideas of a priest may be reflected in his diary. Such a diary offers primary information on the doctrines, practices, propagation, and faith of Buddhism.
The Nichijō shōnin nikki 日乗上人日記 (Diary of the holy priest Nichijō) describes his daily life after he was invited to Mito 水戸 by Mitsukuni 光圀, the second lord of the Mito domain, and he made a conversion to Buddhism. Although it mostly mentions his actions and beliefs, the diary introduces his efforts to propagate and convert by sermons. It tells us the forms of conversion, the level of converted people and the Mitos, especially the faith of the ladies in Mito. Most lectures aimed at conversion by Nichijō are held after his sermon, and not only Lotus Sutra believers but also others attended the lectures. Nichijō’s sermon on the Lotus Sutra offers to convert people who do not belong to any religion.
