The fox changes his skin, but keeps the rogue.
More German Proverbs:
Three women, three geese, and three frogs, make a fair.German
What is sport to the cat is death to the mouse.
German
One cannot wash a blackamoor white.
German
He who would succeed at court, must lie sometimes low, sometimes high.
German
A person has learned much who has learned how to die.
German
There's seldom a cake but there's more of the make.
German