Give a rogue an inch, and he will take an ell.
More Danish Proverbs:
Every one rakes the fire under his own pot.Danish
He is most cheated who cheats himself.
Danish
He who knows a knave, makes no bid for him.
Danish
A moneyless man goes fast through the market.
Danish
Ask advice of your equals, help of your superiors.
Danish
Lords and fools speak freely.
Danish