A barking dog never bites
Making threats but not carrying them out. The idea that a dog that vocalizes disapproval will not attack is more poetry than truth, as an examination of any hospital emergency room records will show. This anecdote is relevant: a candidate for local political office went from door to door to solicit votes. Ringing a doorbell, he was greeted by a woman restraining a large dog that was barking loudly. When the candidate hesitated, his assistant encouraged him to stay, saying, “Don't you know the proverb ‘a barking dog never bites'?” “Yes,” said the candidate, “I know the proverb, and you know the proverb, but does the dog know the proverb?” (Barking dogs figure in another phrase: “My dogs are barking” means that my feet hurt.)