Nichiren Daishonin states in “On Remonstrating with Hachiman”:
India was called the land of the moon. It is a name, indicating the advent of Shakyamuni Buddha. Fuso is the name for ancient Japan, the land of the rising sun. Indeed, how could a sage not appear in this land? The moon travels from west to east, which is a sign of the Buddhism that originated in India spreading to the East. The sun rises in the east, which is an auspicious sign of the Buddhism that emerged in Japan gradually returning to India. Moonlight, when compared to the sun, is not as brilliant. Shakyamuni Buddha expounded the true teaching for only eight years. Sunlight is brighter than the light of the moon, and this signifies that the Buddhist teaching [of Nichiren Daishonin] in Japan shall illuminate the infinite darkness of the fifth Five-hundred-year Period.

宗祖日莲大圣人于《谏晓八幡抄》曰:
天竺国谓月氏国，为应佛出现之名也。扶桑国谓日本国，岂不出圣人乎。月由西向 东，月氏之佛法东流之相也。日自东而出，日本之佛法返月氏之瑞相也。月光不明，在世仅八年也。日之光明胜月，照耀五五百岁长暗之瑞相也。

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