Fool me once, shame on you; fool me twice, shame on me

Fool me once, shame on you; fool me twice, shame on me.

proverb You should be hesitant to trust someone who has already tricked you. Is Ralph just going to pop out from behind that door again? Come on, fool me once, shame on you; fool me twice, shame on me.
See also: fool, on, shame
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

Fool me once, shame on you; fool me twice, shame on me.

Prov. After being tricked once, one should be wary, so that the person cannot trick you again. Fred: Would you like a can of peanuts? Jane: The last can of peanuts you gave me had a toy snake in it. Fred: This one really is peanuts. Jane: Fool me once, shame on you; fool me twice, shame on me.
See also: fool, on, shame
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.
See also: