Kimi kouru namida no toko ni michinureba miotsukushi to zo ware wa narinuru - Kokin Wakashu(English Translation & Meaning)

君恋ふる涙の床に満ちぬれば
みをつくしとぞ我はなりぬる

Roma-ji: Kimi kouru namida no toko ni michinureba miotsukushi to zo ware wa narinuru
English Translation: Since the tears I shed
for love of you have filled
the bed where I lie,
I have now become a channel-post,
spent entirely for you.
Meaning: The tears I weep in longing for you have filled my bed like a sea, and I have become a channel marker standing in it, wholly spent for your sake.
Commentary: Book Twelve Love Poems II 567

Headnote: "A poem from the poetry contest held at the residence of the Empress in the Kanpyō era"
The poet says that the tears he sheds from longing have flooded his bed like a sea, so that he has become a channel marker standing within it, utterly spent. To the exaggeration of tears as a sea is added the pun on miotsukushi, both "channel marker" and "exhausting oneself," wittily expressing the suffering of giving oneself entirely to love. It was composed for the Kanpyō-era Empress's poetry contest and is placed within the run of poems from that contest.
Fujiwara no Okikaze was a poet of the early Heian period, a great-grandson of Fujiwara no Hamanari and the son of Fujiwara no Michinari. He served as Secretary of Sagami and Provisional Senior Secretary of Shimōsa. He was also known as a master of the koto and is one of the Thirty-Six Poetic Immortals.

First line, "kimi kouru": "longing for you," modifying "tears" in the second line. Poem 572 of this book also begins with "kimi kouru," and these two poems on tears from the same contest echo each other.
Second line, "namida no toko ni": tears flowing onto the bed, the bed where he sleeps alone.
Third line, "michinureba": nure is the perfective form of the completion auxiliary nu, and with the causal ba it means "since they have filled." It is an exaggeration likening tears to the tide of the sea.
Fourth line, "miotsukushi to zo": miotsukushi is a pun on "channel marker," a stake set to mark a waterway, and "exhausting oneself." The image of himself as a channel marker in a sea of tears overlaps with giving himself entirely to love. The binding particle zo pairs with the final line.
Fifth line, "ware wa narinuru": nuru is the attributive resolving zo, closing with "I have finally become so."
Author: Fujiwara no Okikaze
Source: Kokin Wakashu
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