classic waka stream

堰きとむる岩間の水もおのづから
下には通ふものとこそ聞け
Roma-ji

Sekitomuru iwama no mizu mo onozukara shita ni wa kayou mono to koso kike

English Translation
Even water dammed
in the gaps between the rocks
will of its own course
flow through underneath, they say —
this much I have heard is so
Meaning
I have heard that even water dammed among the rocks will find its own way through underneath; so too our hearts, though kept apart, should reach each other beneath the surface.
Commentary
Book Eight Love Poems II 243

The poet says she has heard that even water dammed among the rocks will flow through underneath of its own accord, appealing that a love kept apart by watching eyes should still meet in the depths of the heart. The hope of a love blocked by obstacles is entrusted to flowing water.

The first line, "sekitomuru" (dammed up), suggests obstacles that hinder love.
The second line, "iwama no mizu mo," uses "mo": even water held back among the rocks. As with the torrent checked by a rock in poem 229 of Book Seven, the rock stands for the obstacles of love.
The third line, "onozukara" (of its own course), shows a flow that cannot be stopped however it is hindered.
The fourth line, "shita ni wa kayou," overlays water flowing beneath with hearts that reach each other without showing it. It shares the conceit of the mountain stream flowing under ice in poem 227 of Book Seven.
The final line, "mono to koso kike," forms a kakari-musubi of "koso" with the perfective "kike," declaring firmly that this is what she has heard and urging the beloved's heart.
Source
Shika Wakashu
Prev Poem
Tsune yori mo tsuyukekarikeru koyoi kana kore ya aki tatsu hajime naruramu
Next Poem
Au koto wa mabara ni ameru Iyosudare iyoiyo ware o wabisasuru kana