Matsuyama ni nami takashi to wa miteshikado kyō no nagame wa tada naranu kana - Izumi Shikibu Nikki(English Translation & Meaning)

松山に波高しとは見てしかと
今日の詠めはたゝならぬかな

Roma-ji: Matsuyama ni nami takashi to wa miteshikado kyō no nagame wa tada naranu kana
English Translation: That the waves rise high
over Matsuyama, I had seen
long before, and yet
my brooding in today's long rain
is no common thing at all
Meaning: I had seen well enough that high waves were washing over the Pine Mountain, yet my brooding in today's long rain is far from ordinary.
Commentary: 15 The Carriage at the Gate and the Pines of Sue

The night after their moonlit exchange, the prince came to Izumi Shikibu, but she did not know it. Several households lived in different parts of the house, and when his attendant saw the carriage of someone who had come to visit another resident and said, "There seems to be a visitor; there is a carriage," the prince said, "Very well, let us go back," and left. He was displeased to think the rumors were true, yet he had no wish to end things altogether, and so he sent her a letter.
The woman is Izumi Shikibu, daughter of Ōe no Masamune and, as the wife of Tachibana no Michisada, Governor of Izumi, mother of Koshikibu no Naishi. The Prince of the Dazaifu is Prince Atsumichi, fourth son of Emperor Reizei, so called because he served as Governor-General of the Dazaifu.
The prince wrote, "Did you at least hear that I came last night? It grieves me to think you may not even have known," and sent this poem. It was raining at the time.
Thinking it strange, and wondering whether someone had told him a groundless tale, Izumi Shikibu replied with "Kimi o koso sue no matsu to wa omoitsure hitoshinami ni wa tare ka koyubeki."
The source poem is from the Eastern Songs of the Kokin Wakashū, a vow saying that if I ever turned my heart from you to another, the waves would wash over the Pine Mountain of Sue, which no wave ever crosses.

The first three lines mean "I had seen that waves ran high over the Pine Mountain, yet," drawing on the source poem to express, through the image of waves crossing the mountain, his suspicion that she had another man; a past-tense auxiliary and an adversative particle frame the line.
The lower verses mean "my brooding in today's long rain is no ordinary thing," with "nagame" meaning both long rain and gazing. He had heard the rumors, but what he feels today, having seen the carriage at her gate, is something else again, and through the falling rain he conveys his jealousy and grief.
Author: Prince Atsumichi
Source: Izumi Shikibu Nikki
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