Var.: Легко сказка сказывается, да нелегко дело делается
Cf: Easier said than done (Am., Br.). Easy to say and hard to do (Br.). Saying and doing are two different things (Am.). Saying and doing are two things (Am., Br.). Sooner said than done (Am.). There is a difference between saying and doing (Br.)Русско-английский словарь пословиц и поговорок. Академик.ру. 2013.