Count not your chickens before they are hatched.
More German Proverbs:
God forgives sinners, otherwise His heaven would be empty.German
The best friends are in one's purse.
German
He who stops half way is only half in error.
German
It is better the child should cry than the father.
German
Beauty is the eye's food but the soul's sorrow.
German
You cannot hang a man twice.
German