He. Never until this night have I been stirred.
The elaborate starlight throws a reflection
On the dark stream,
Till all the eddies gleam;
And thereupon there comes that scream
From terrified, invisible beast or bird:
Image of poignant recollection.

She. An image of my heart that is smitten through
Out of all likelihood, or reason,
And when at last,
Youth's bitterness being past,
I had thought that all my days were cast
Amid most lovely places; smitten as though
It had not learned its lesson.

He. Why have you laid your hands upon my eyes?
What can have suddenly alarmed you
Whereon 'twere best
My eyes should never rest?
What is there but the slowly fading west,
The river imaging the flashing skies,
All that to this moment charmed you?

She. A Sweetheart from another life floats there
As though she had been forced to linger
From vague distress
Or arrogant loveliness,
Merely to loosen out a tress
Among the starry eddies of her hair
Upon the paleness of a finger.

He. But why should you grow suddenly afraid
And start -- I at your shoulder --
Imagining
That any night could bring
An image up, or anything
Even to eyes that beauty had driven mad,
But images to make me fonder?

She. Now She has thrown her arms above her head;
Whether she threw them up to flout me,
Or but to find,
Now that no fingers bind,
That her hair streams upon the wind,
I do not know, that know I am afraid
Of the hovering thing night brought me.

William Butler Yeats

http://www.poemhunter.com/poem/an-image-from-a-past-life/