He has given the hen for the egg.
More German Proverbs:
It is a bad horse that does not earn his fodder.German
In bad luck, hold out; in good luck, hold in.
German
As a tree falls, so shall it lie.
German
Women and maidens must be praised, whether truly or falsely.
German
If the shoe fits, wear it.
German
No one can complain of the sea who twice suffers shipwreck.
German