Au koto o koyoi to omowaba yūzukuhi iru yama no ha mo ureshikaramashi - Kinyo Wakashu(English Translation & Meaning)

逢ふことを今宵と思はば夕づく日
入る山の端も嬉しからまし

Roma-ji: Au koto o koyoi to omowaba yūzukuhi iru yama no ha mo ureshikaramashi
English Translation: If I could believe
that tonight we two would meet,
the evening sun
sinking down behind the hills
would be a joy to behold
Meaning: If only I could think that tonight would be the night we meet, then even the evening sun setting behind the hills would be a joy to see.
Commentary: Book Eight Love Poems II 427

If the poet knew that tonight was the night they would meet, then even watching the evening sun sink behind the hills would bring joy. Through a contrary-to-fact supposition, the poem turns inside out the loneliness of facing dusk with no promise of a meeting.
Dusk is the hour of waiting for a lover's visit, and where poem 423 in this book sang of the pain of parting at dawn, this poem sings of waiting for the dusk when a meeting would begin.

First line, 'au koto o', means meeting my beloved.
Second line, 'koyoi to omowaba', means if I could think it tonight, a supposition formed by the irrealis with ba.
Third line, 'yūzukuhi', means the evening sun.
Fourth line, 'iru yama no ha mo', means even the ridge of the hills where it sets, the particle mo adding the sense of even a sunset that would usually be lonely.
Final line, 'ureshikaramashi', means would be joyful, using the contrary-to-fact mashi in answer to omowaba in the second line.
Source: Kinyo Wakashu
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