Context: King Richard, furthering his design to make fast his throne, asks Elizabeth, the widow of Edward IV, how he should woo her daughter, also named Elizabeth. The widow declares that such a marriage is impossible, that he would be going to her daughter with the blood of her brothers on his hands. Richard assures her that he now means her family only good. But the widow insists that her reasons for hating him are "Too deep and dead, poor infants, in their graves." Richard, stung to the quick, rebukes her:
Harp not on that string madam, that is past.
Harp on it still shall I till heart-strings break.