believe one's ears

believe (one's) ears

To trust or have faith in something that one has heard. Well, believe your ears because I did get that big promotion!
See also: believe, ear

believe one's ears

Also, believe one's eyes. Trust one's own hearing or sight, as in We couldn't believe our ears when we heard that Gene was accepted at Stanford, or I couldn't believe my own eyes when the movie stars walked in. This expression of incredulity is nearly always stated negatively, as in the examples. [Early 1600s]
See also: believe, ear