promise the moon

promise (one) the moon

To promise one something that cannot be done. Your clients will come to distrust you if you keep promising them the moon.
See also: moon, promise
Farlex Dictionary of Idioms.

promise the moon (to someone)

 and promise someone the moon
to make extravagant promises to someone. Bill will promise you the moon, but he won't live up to his promises. My boss promised the moon, but never gave me a raise.
See also: moon, promise
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

promise the moon

If someone promises the moon, they promise to do or give things that they cannot in fact give. Politicians promise the moon at election time, but do they deliver once they're elected?
See also: moon, promise
Collins COBUILD Idioms Dictionary, 3rd ed.

promise (somebody) the ˈmoon/ˈearth/ˈworld

(informal) make very big or impossible promises that you are unlikely to keep: He promised her the moon, but after ten years of marriage they hardly had enough to live on.
See also: earth, moon, promise, world
Farlex Partner Idioms Dictionary
See also:
  • promise (one) the moon
  • promise someone the moon
  • promise the moon/earth/world
  • breach of promise
  • keep (one's) promise
  • a promise is a promise
  • keep a promise
  • be over the moon
  • over the moon
  • man in the moon, (no more than) the
References in periodicals archive
Don't make inflated claims or promise the moon and stars in a mass e-mail, and people will more likely respond to your message.
Be wary of PEO contracts that promise the moon; the reality is that the courts and administrative agencies have established some clear guidelines about risk transfer.
-- Medicalsoftware salespeople have been known to promise the moon:
-- Medical software salespeople have been known to promise the moon.
Few products can promise the moon and deliver it, especially to a naturally skeptical bunch of builders.
Bush likes to promise the moon, as he did when he pledged to eradicate global terrorism.
A lesson for all is to know if your product is truly suited to the industry and client it is supposed to serve before you promise the moon.
Don't promise the moon. Offer to help enlighten a client as to the future's possibilities, but never promise to predict it.
In an age when most musicals promise the moon -- or at least an airborne helicopter -- it's refreshing to see a show with as few pretensions as Tommy Tune and Sandy Duncan's "Two for the Show." This revue was stitched together from the remnants of "Easter Parade"; Tune and Duncan had been working up a live version of the 1948 film, with hopes of taking it to Broadway.
They can promise the moon, but Joe Sixpack is not going to believe they can deliver the moon."