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!" That consultant has all these radical ideas that he wants to pitch to the boss, and I've warned him—if you can't walk the walk, don't talk the talk.