The sky is darkening like a stain; Something isgoing to fall like rain, And it won't be flowers.

-Auden,W(ystan) H(ugh)
  'The Witness'.

The unbought grace of life, the cheap defence of nations, the nurse of manly sentiment and heroic enterprise isgone! it isgone, that sensibility of principle, that chastity of honour, which felt a stain like a wound, which ennobled whatever it touched, and under which vice itself lost half its evil, by losing all its grossness.

-Burke, Edmund
  Reflections on the Revolution in France.

And let their liquid siftings fall To stain the stiff dishonoured shroud.

-Eliot,T(homas) S(tearns)
  'Sweeney among the Nightingales'.

Money, wife, is the true fuller's earth for reputations, there is not a spot or a stain but what it can take out.

-Gay,John
  The Beggar's Opera, act1, sc.9.

Love is a universal migraine A bright stain on the vision Blotting out reason.

-Graves, Robert von Ranke
  'Symptoms of Love'.

I am the daughter of Earth and Water, And the nursling of the Sky; I pass through the pores of the ocean and shores; I change, but I cannot die, For after the rain when with never a stain The pavilion of Heaven is bare, And the winds and sunbeams with their convex gleams Build up the blue dome of air, I silently laugh at my own cenotaph, And out of the caverns of rain, Like a child from the womb, like a ghost from the tomb, I arise and unbuild it again.

-Shelley, Percy Bysshe
  'The Cloud'.

Lost Angel of a ruined Paradise! She knew not 'twas her own; as with no stain She faded, like a cloud which had outwept its rain.

-Shelley, Percy Bysshe
Adonais, stanza10.

   He has out-soared the shadow of our night; Envyand calumnyand hate and pain, And that unrest which men miscall delight, Can touch him not and torture not again; From the contagion of the world's slow stain He is secure, and now can never mourn A heart grown cold, a head grown grey in vain.

-Shelley, Percy Bysshe
Adonais, stanza 40.