Old swine have hard snouts, old oxen hard horns.
More Danish Proverbs:
When every one minds his own business the work is done.Danish
He who flees, proves himself guilty.
Danish
The earth is always frozen to lazy swine.
Danish
Love's plant must be watered with tears, and tended with care.
Danish
Every day hath its night, every weal its woe.
Danish
Wisdom is the least burdensome travelling pack.
Danish