classic waka stream

思ひつつ寝ればかもとなぬばたまの
一夜もおちず夢にし見ゆる
Roma-ji

Omoitsutsu nureba ka motona nubatama no hitoyo mo ochizu ime ni shi miyuru

English Translation
Is it because
I fall asleep longing,
that for no reason
through the jet-black nights, not one missed,
she appears in my dreams
Meaning
Is it because I fall asleep thinking of her that, for no reason at all, she appears in my dreams every single night?
Commentary
Book Fifteen Exchange Poems of Nakatomi no Yakamori and Sano no Otogami no Otome 3738

Headnote continued from the preceding poem: "Poems exchanged between Nakatomi no Ason Yakamori and Sano no Otogami no Otome"
He wonders whether it is because he sleeps thinking of her that his wife appears in his dreams every night without fail. He seeks the reason for her appearing in the strength of his own longing, and one senses that the nightly dreams only intensify his yearning. The third line onward is nearly the same as from the third line of 3647 in the first half of the book, by an envoy to Silla, so that the laments of spouses far apart echo across the two halves.
The author, Nakatomi no Yakamori, was a son of Nakatomi no Azumahito, from the Nakatomi clan in charge of the rites of the gods. He was exiled to Echizen Province for an offense, but was later pardoned and returned to the capital.
A left note reads "the above fourteen poems are by Nakatomi no Ason Yakamori"; the fourteen poems from 3731 to 3744 of this book were sent by Yakamori to the young woman from his place of exile. The latter half of this book contains sixty-three poems exchanged between Nakatomi no Yakamori and Sano no Otogami no Otome. According to the book's table of contents, when Yakamori took as his wife the young woman, a lady-in-waiting of the palace storehouse office, he was exiled to Echizen Province by imperial decree. The place of exile is thought to be Ajimano in Echizen, near present-day Echizen City, Fukui Prefecture.

First line, "omoitsutsu": while thinking of my wife continually.
Second line, "nureba ka motona": "nureba" is a definite condition and "ka" an interrogative binding particle resolved by the attributive "miyuru"; "motona" means for no reason, helplessly.
Third line, "nubatama no": a pillow word for "night."
Fourth line, "hitoyo mo ochizu": "otsu" means to be left out: not missing a single night. The same as the fourth line of 3647 of this book.
Fifth line, "ime ni shi miyuru": "ime" is dream and "shi" emphatic; answering "ka" in the second line, it ends in the attributive form.
Author
Nakatomi no Yakamori
Source
Manyoshu
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