In 1657, he returned to his native place and started popularizing neo-Confucianism; in 1675 and 1680, he was reprimanded by the bakufu (Japanese feudal government headed by a shogun) for the description about Christianity in the entry of Kiyohide NAKAGAWA, a retainer of the Toyotomi clan, in his book 'Nihon kokon jinbutsushi' and sentenced to several years' imprisonment in Iwakuni.
1657年に帰郷して、朱子学を広めたが、1675年と1680年との2度にわたって著作「日本古今人物史」で、豊臣氏家臣・中川清秀のキリスト教関係記述部分について、幕府から指摘を受け、岩国で数年間の禁錮に処された。