Chitose made sumamu izumi no soko ni yo mo kage o narabemu to omoishi mo seji - Kinyo Wakashu(English Translation & Meaning)

千年まですまむ泉の底によも
影を並べむと思ひしもせじ

Roma-ji: Chitose made sumamu izumi no soko ni yo mo kage o narabemu to omoishi mo seji
English Translation: In this spring that will
run clear and dwell a thousand years,
upon its bottom
I would never have thought to
set my image side by side
Meaning: I would never have dreamed that I would come to cast my reflection side by side with yours on the floor of this spring, which will stay clear for a thousand years.
Commentary: Book Nine Miscellaneous Poems I 589

Never, the poet says, would one have thought to set one's own image side by side on the floor of this spring, which will stay clear and be dwelt beside for a thousand years. The pivot between sumu, to be clear, and sumu, to dwell, expresses surprise and humility at finding oneself reflected in the spring of a long-flourishing house.
The spring seems to be one in a mansion garden, and the poem can also be read as carrying a blessing on the house's prosperity.

First line, 'chitose made', means for a thousand years, praising the long life of the spring or the house.
Second line, 'sumamu izumi no', is a pivot in which suma means both the water being clear and living there, left in kana.
Third line, 'soko ni yo mo', means at its floor, surely not, the adverb yo mo answering the negative conjectural ji in the final line.
Fourth line, 'kage o narabemu to', means to set my image side by side, using the volitional mu. It is a hypermetric line.
Final line, 'omoishi mo seji', means I would never have thought, the particles shi and mo adding emphasis, closing with the negative conjectural ji in answer to yo mo in the third line.
Source: Kinyo Wakashu
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