What is the good of a sundial in the shade?

Similar English and Irish sayings:

Do not cut down the tree that gives you shade Do not cut down the tree that gives you shade
Honour the tree that gives you a shade Honour the tree that gives you a shade
The good or ill hap of a good or ill life, is the good or ill choice a good or ill wife The good or ill hap of a good or ill life, is the good or ill choice a good or ill wife

Proverbs and English sayings