Never judge from appearances.
More Traditional Proverbs:
One who looks for a friend without faults will have none.Traditional
Where the law is uncertain there is no law.
Traditional
Comparing apples to oranges.
Traditional
All criminals turn preachers under the gallows.
Traditional
There was never a scabby sheep in a flock that didn't like to have a comrade.
Traditional
You can't make an omelette without breaking eggs.
Traditional