When a dove begins to associate with crows its feathers remain white but its heart grows black.

Related:

• If the dove chooses to fly with the hawks his feathers
  stay white but his heart turns black...
• A proverb never lies, it is only its meaning which deceives.
  German...
• A country can be judged by the quality of its proverbs.
  German...
• Revenge does not long remain unrevenged.
  German...
• Who begins too much accomplishes little. --
  German...
• When the blossom grows white the potatoes
  are good...
• A heart in love with beauty never grows old. --
  Ancient Turkish...
• A heart in love with beauty never grows old.
  Turkish...
• Who takes the child by the hand takes the mother by the heart.
  German...