Var.: Лень добра не делает. Лень - мать всех пороков
Cf: Doing nothing is doing ill (Am., Br.). An idle brain is the devil's workshop (Am., Br.). Idleness breeds trouble (Am.). Idleness is the mother of evil (mischief, sin) (Am.). Idleness is the parent of many vices (Am.). Idleness is the parent of vice (Br.). No good comes of idleness (Br.). Of idleness comes no goodness (Am.). Sloth is the mother of vice (Am.). Trouble springs from idleness (Am.)Русско-английский словарь пословиц и поговорок. Академик.ру. 2013.