classic waka stream

今日ぞ知る鷲の高嶺に照る月を
谷川汲みし人の影とは
Roma-ji

Kyō zo shiru washi no takane ni teru tsuki o tanigawa kumishi hito no kage to wa

English Translation
Today at last I know,
the moon that shines upon the high
peak of Vulture Mount
is the very form of one
who drew water from the stream
Meaning
Today I have come to know that the moon shining on the high peak of Vulture Peak is the form of the one who once drew water from the valley stream.
Commentary
Book Ten Miscellaneous Poems II 636

Today at last the poet knows that the moon shining on the high peak of Vulture Peak is the figure of the one who once drew water from the valley stream to serve a hermit. Drawing on the Lotus Sutra's Devadatta chapter, which tells how in a former life the Buddha served a hermit and obtained the Lotus Sutra after hardships such as drawing water, the poem likens the Buddha preaching on Vulture Peak to the moon and turns its thoughts to his former life.
Where the preceding poem, 635, sang of carrying firewood from the same story, this poem sings of drawing water, and the two form a pair. The opening line kyō zo shiru echoes ima zo shiru in the first line of 621 in this book.
The author, Morotoki, is Minamoto no Morotoki, a son of the Minister of the Left Minamoto no Toshifusa, who became Provisional Middle Counselor. He left the diary Chōshūki.

First line, 'kyō zo shiru', means today I know, the particle zo answered by the attributive shiru; the poem breaks after the first line. It echoes ima zo shiru in the first line of 621 in this book.
Second line, 'washi no takane ni', means on the high peak of Vulture Peak, the mountain where the Buddha preached the Lotus Sutra. It also echoes washi no yamakaze in the second line of 634 in this book.
Third line, 'teru tsuki o', means the shining moon, standing for the Buddha as he preaches.
Fourth line, 'tanigawa kumishi', means who drew from the valley stream, pointing to the hardships of the Buddha's former life told in the Devadatta chapter. It pairs with ninau takigi in the preceding poem, 635, and high peak and valley stream are also set against each other.
Final line, 'hito no kage to wa', means that it is the figure of that person, an inversion turning back to shiru in the first line.
Author
Minamoto no Morotoki
Source
Kinyo Wakashu
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