Masuge ouru yamashitamizu ni yadoru yo wa tsuki sae kusa no iori o zo sasu - Senzai Wakashu(English Translation & Meaning)

真菅生ふる山下水に宿る夜は
月さへ草の庵をぞさす

Roma-ji: Masuge ouru yamashitamizu ni yadoru yo wa tsuki sae kusa no iori o zo sasu
English Translation: On a night it lodges
in a stream below the hills
where the sedges grow,
even the moon has shut itself
in a hermitage of grass
Meaning: On a night when it lodges in the stream beneath the mountain where sedges grow, even the moon seems to shut itself into a hut of grass, its light shining within.
Commentary: Book Sixteen Miscellaneous Poems I 1017

Headnote: "On the theme "The moon shines on mountain water""
This poem was composed on the theme "the moon shines on mountain water." On nights it lodges in the stream below the hills where sedges grow, even the moon shuts itself in a grass hut, he says. When the moon is reflected in the water flowing in the mountain's shade, surrounded by thick sedges, it seems that the moon, like a traveler, has taken lodging in a grass hut and shut its door. "Sasu" means both to shut a door and for light to shine in.
The author, "Hōgen Chōshin," was a monk of the late Heian period who held the rank of hōgen, and his biography is not known in detail.
It shares with "ato naki mizu ni yadoru tsuki" in 1012 of this book the moon lodging in water, and here further sees the lodging moon as a traveler staying in a grass hut.

First line, "masuge ouru": "where sedges grow thick," with "ma" an honorific prefix. It is a hypermetric line of six syllables.
Second line, "yamashitamizu ni": "in the water flowing in the mountain's shade."
Third line, "yadoru yo wa": "on nights when the moon's image is reflected in the water," layering the sense of taking lodging. It answers "yadoru tsuki kana" in the fifth line of 1012 of this book.
Fourth line, "tsuki sae kusa no": "sae" is an additive particle, "not only the traveler but even the moon."
Fifth line, "iori o zo sasu": "sasu" is a pivot word meaning both to shut a door and for moonlight to shine in. "Zo" is an emphatic binding particle closing with the attributive "sasu."
Author: Chōshin
Source: Senzai Wakashu
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