Omoiki ya aimishi yowa no ureshisa ni nochi no tsurasa no masarubeshi to wa - Kinyo Wakashu(English Translation & Meaning)

思ひきや逢ひ見し夜半の嬉しさに
後のつらさのまさるべしとは

Roma-ji: Omoiki ya aimishi yowa no ureshisa ni nochi no tsurasa no masarubeshi to wa
English Translation: Could I have known it—
that the joy of the night
when we lay together
would be surpassed by the pain
that was to follow after
Meaning: Could I ever have imagined it, that the pain afterward would come to outweigh the joy of the night we spent together?
Commentary: Book Eight Love Poems II 441

The poet never imagined that the pain that followed would outweigh the joy of the night they met. The poem conveys the irony of a love whose suffering only deepens after the meeting is won.
Poem 459 in this book sings that a rare night of meeting feels like a dream while only the longing is real, sharing with this poem the fleetingness of the joy of meeting and the pain that comes after.

First line, 'omoiki ya', means did I ever think so, no, I never did, the past ki followed by the rhetorical ya. The poem breaks after the first line, and by inversion it leads on to to wa in the final line.
Second line, 'aimishi yowa no', means of the night we met, aimiru meaning for a man and woman to be together.
Third line, 'ureshisa ni', means compared with the joy.
Fourth line, 'nochi no tsurasa no', means the pain that came after.
Final line, 'masarubeshi to wa', means that it would surpass, using the expectational beshi and returning by inversion to omoiki ya in the first line.
Source: Kinyo Wakashu
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