if you can't walk the walk, don't talk the talk

if you can't walk the walk, don't talk the talk

Do not make claims that you are not able to back up with equivalent actions. Anybody can run their mouth like that, but I believe that if you can't walk the walk, don't talk the talk. A: "Bah, that's not impressive. I could do that with one arm tied behind my back!" B: "Go on then, show us. But if you can't walk the walk, then don't talk the talk!"
See also: if, talk, walk
Farlex Dictionary of Idioms.
See also:
  • not for a second
  • not for a minute
  • not for a moment
  • aint
  • ain't
  • not exactly
  • not for a instant
  • not for a/one minute/moment/second/instant
  • by no means
  • not by any means