In John Augustus Stone’s melodrama Metamora; or, the Last of the Wampanoags, first performed in 1829, the heroine Oceana is so concerned about her lover, Walter, that she indulges in an aside: “Be still my throbbing heart.” Today a variant of the line—“Be still, my beating heart”—is a well circulated cliché. Was Metamora the coining of it? After a quick check of Bartlett’s and a brief poke through the database Literature Online, I suspect that it was. Of course, to prove that a phrase has no antecedent is to prove an absolute negative, which is awfully hard; a single counterexample will topple my hypothesis.
But if I’m right, then the turn of phrase permeated the culture without the assistance of print, because the play was never published while it was popular. The star of Metamora, Edwin Forrest, awarded a prize to the play’s author, and he considered that by paying the prize money he had purchased the play’s copyright. To ensure that it would not serve as a star vehicle for anyone else, Forrest prevented publication, and he prevented it so well that the play didn’t appear in print until 1941. In fact, act 4—the one that contains the line “Be still my throbbing heart”—didn’t appear in print until 1962.
In The Name of War, scholar Jill Lepore notes that lines from Metamora “became household words,” quoted by boys playing Indian and sentimental Americans of all ages. So it seems plausible, if exceptional, that the beating-heart line might have entered the popular linguistic subconscious by no other means than being spoken from stage.