Omowanu o omou to iwaba ōno naru mikasa no mori no kami shi shirasamu

思はぬを思ふと言はば大野なる
御笠の杜の神し知らさむ

Roma-ji: Omowanu o omou to iwaba ōno naru mikasa no mori no kami shi shirasamu
English Translation: If I did not love,
yet should say I loved you true,
there in Ōno stands
the grove of Mikasa's god,
and the god would surely know
Meaning: If I were to say I love you when I do not, the god of the Mikasa grove at Ōno would surely know it.
Commentary: Book Four Love Poems 561

Headnote continued from the preceding poem: "Four love poems by Ōtomo no Sukune Momoyo, Senior Secretary of the Dazaifu"
If he were to claim a love he does not feel, the god of the Mikasa grove at Ōno would see through it; he swears by the god that his love is true. By calling on a god near the Dazaifu, he makes his vow concrete and weighty. Poem 655 in this book shares the same first two lines, "If I did not love, yet should say I loved," so that the same words of oath appear in another poem.
The author, Ōtomo no Momoyo, was an official of the Ōtomo clan who served under Ōtomo no Tabito as Senior Secretary of the Dazaifu.

First line, "If I did not love," uses the concessive o: though I do not love.
Second line, "yet should say I loved you true," uses the hypothetical -ba: if I said I loved.
Third line, "there in Ōno stands," names Ōno in Chikuzen, the area around Mount Ōno north of the Dazaifu; naru is a contraction of ni aru.
Fourth line, "the grove of Mikasa's god," names the Mikasa grove at Ōno, held to be where a god dwelt.
Fifth line, "and the god would surely know," uses the emphatic shi and shirasu, honorific of shiru, "to know": the god would see it.
Author: Ōtomo no Momoyo
Source: Manyoshu
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