備えあれば憂いなし (そなえあればうれいなし): if you are prepared you don't have to worry; it's good to have a shelter against every storm

if you are prepared you don't have to worry; it's good to have a shelter against every storm

Close to 転ばぬ先の杖, but about readiness bringing calm rather than avoiding the fall: once prepared, you simply stop worrying.

The same saying in Chinese: 有备无患

A Japanese proverb (ことわざ)