classic waka stream

Unknown to any,
I send my thoughts of you there,
westward, entrusting
them to the moon as it leans
over and goes down the sky

Meaning
Unknown to anyone, I send my longing for you westward, entrusting it to the moon as it leans down the sky.
Commentary
Volume Nine: The Muster at Mikusa

 Many in the capital took heart at word that the Taira had come back up as far as Fukuhara. Among those there, the Bishop Zenshin of the second rank had for years shared a residence with the Kajii prince, and the two kept up a correspondence.
 A letter came from the prince in the capital. He wrote at length—that he supposed the hardships of being away must be great, and that the capital itself was far from quiet—and at the end he added a poem. This is it.
 When the bishop had read it he pressed the letter to his face and wept.

 Sonata, "that side," is the west: Fukuhara. He looks west from the capital and thinks of what is there.
 The "leaning moon" is the moon going down in the west. Since the moon travels west, a thought entrusted to it will reach Fukuhara. To a man he has no means of reaching, he sends his feeling by the motion of a heavenly body—the same device as Yasuyori's message entrusted to the sea wind in Volume Two.
 But "the moon leaning west" is the very phrase written at the head of the Taira petition in Volume Seven, where it declared the house's ruin. Here it serves as a vehicle for affection, and yet the direction it travels is still the direction of setting. It is a consoling poem whose destination is fixed.
 That the bishop wept into the letter suggests he read that far into it. A prince remaining in the capital sends a man on the Taira side a feeling he cannot state openly. "Unknown to any" carries his position exactly.

hito shirezu……without anyone knowing.
sonata……that direction; here, Fukuhara in the west.
shinobu……to long for; also to keep hidden.
tagau……to set alongside; here, to entrust.
katamuku tsuki……the moon leaning down toward setting.
Kajii no Miya……the princely abbot of the Kajii cloister on Mount Hiei.
Zenshin……a bishop of the Taira house.
dōshuku……sharing a residence in a temple.
inshin……correspondence, news.
Source
Heike Monogatari
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