Chikai o ba chihiro no umi ni tatou nari tsuyu mo tanomaba kazu ni irinan - Senzai Wakashu(English Translation & Meaning)

誓ひをば千尋の海にたとふなり
露も頼まば数に入りなん

Roma-ji: Chikai o ba chihiro no umi ni tatou nari tsuyu mo tanomaba kazu ni irinan
English Translation: Kannon's great vow
is likened to the ocean
a thousand fathoms deep;
trust it but a dewdrop's worth
and we will be counted in
Meaning: Kannon's vow is likened to a sea a thousand fathoms deep. Then if we trust in it even by a dewdrop's worth, surely we will be counted among the saved.
Commentary: Book Nineteen Buddhist Poems 1216

Headnote: "Composed on the line of the Universal Gate chapter, the great vow is deep as the sea, when the emperor called for a hundred-poem sequence"
When he called for a hundred-poem sequence, he composed this on the line of the Universal Gate chapter saying that Kannon's great vow is as deep as the sea. The vow is likened to a sea a thousand fathoms deep; trust it even a dewdrop's worth and we will be counted among the saved, he says. If the vow is as deep and wide as the sea, it must take in without fail even a faith as slight as a dewdrop, and through this contrast of the vast sea and the tiny dewdrop he sings of the boundless mercy of Kannon.
The author, "Poem of Retired Emperor Sutoku," is a composition of Sutoku, the first son of Emperor Toba, who became the seventy-fifth emperor. He loved poetry, called for the Kyūan Hundred-Poem Sequences and commanded the compiling of the Shika Wakashū. Defeated in the Hōgen Disturbance, he was exiled to Sanuki and died there.
The next poem, 1217, is from the same hundred-poem sequence, as its headnote says, and the poems of that occasion continue. 1238 in this book also sings of Kannon's vow; where this poem likens the vow to the sea, that one likens it to a spring that makes a withered branch bloom.

First line, "chikai o ba": "chikai" is Kannon's vow to save all beings, and "o ba" sets the object in relief.
Second line, "chihiro no umi ni": "chihiro" means exceedingly deep, taking up the headnote's "deep as the sea."
Third line, "tatou nari": "it is likened," meaning that the sutra makes this comparison. The poem pauses here.
Fourth line, "tsuyu mo tanomaba": "tsuyu mo" means even the least bit, and the dewdrop contrasts in scale with the sea of the second line.
Fifth line, "kazu ni irinan": "kazu ni iru" means to be numbered among the saved, and "nan," the irrealis of the perfective "nu" with the conjectural "mu," gives "surely we will be."
Author: Retired Emperor Sutoku
Source: Senzai Wakashu
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