One cannot keep peace longer than his neighbour will let him.
More German Proverbs:
Who does not punish evil, invites it.German
A penny saved is two-pence got.
German
Whatever is given to the poor, is laid out of the reach of fortune.
German
The more the well is used, the more water it yields.
German
He who has no enemies has no friends either.
German
Keep well with your neighbours, whether right or wrong.
German