A Magnificat:
My flesh in terror and fire
Rejoices that the Word
Who utters the world out of nothing,
As a pledge of his word to love her
Against her will, and to turn
Her desperate longing to love,
Should ask to wear me,
From now to their wedding day,
For an engagement ring.
W.H. Auden, For the Time Being (about which @ayjay reportedly knows quite a lot)
This is my favorite verse from my objectively-favorite poem (measured by repeated reading).