Nichijin adopted the Shyoretsu school in the interpretation of Konpon kyoten (primal scripture) Hokke-kyo Sutra, and he especially emphasized chapter 16, Nyoraijuryo-hon (Duration of the Life of the Tathagata, chapter 16 of the Lotus Sutra) among Honmon which was regarded as 'Sho' (superior).
根本経典法華経の解釈は勝劣派であるが、「勝」とする本門の内、日陣は特に法華経如来寿量品第十六を重んじる。