Yo no naka ni shirarenu yama ni mi naku tomo tani no kokoro ya iwade omowamu - Gosen Wakashu(English Translation & Meaning)

世の中に知られぬ山に身なくとも
谷の心やいはで思はむ

Roma-ji: Yo no naka ni shirarenu yama ni mi naku tomo tani no kokoro ya iwade omowamu
English Translation: Though you lose your life
on a mountain unknown
to all the world,
would the valley's heart, I ask,
keep silent with its thoughts
Meaning: Even if you were to perish on some mountain unknown to the world, would the heart of the valley keep its thoughts to itself without a word?
Commentary: Book Sixteen Miscellaneous Poems II 1164

Headnote: "Reply, by the former husband."
The poet asks whether, even if the other were to die on a mountain unknown to the world, the valley's heart would keep its thoughts in silence. Taking up the lines of the preceding poem, he mocks the man who visited his wife: just as a valley echoes back, the affair will be known in the end, however one hides in the hills.
It is the reply of the woman's husband to the monk Gachō's poem before it. In the original the poet is given, as for the preceding poem, as the monk Gachō, but since the headnote says "the former husband," it is taken to be the woman's husband's poem.
The poet is the woman's husband named in the headnote, whose name has not come down to us.

The first line, "Yo no naka ni," means "in this world," taking up the third line of the preceding poem.
The second line, "shirarenu yama ni," means "on a mountain unknown," the same as the fourth line of the preceding poem.
The third line, "mi naku tomo," means "even if you perish," taking up the first line of the preceding poem.
The fourth line, "tani no kokoro ya," means "would the valley's heart," bringing in the valley in keeping with the mountain. "Ya" is a rhetorical binding particle closed by the attributive "mu" in the last line.
The last line, "iwade omowamu," means "think on without speaking," with "iwa" echoing both speaking and "iwa," rock, in keeping with the valley. It implies that, like a valley's echo, it will not stay silent.
Source: Gosen Wakashu
Prev Poem: Mi naku tomo hito ni shirareji yo no naka ni shirarenu yama o shiru yoshi mogana
Next Poem: Oto ni nomi kikite wa yamaji asaku tomo iza kumimiten yama no i no mizu