In Scene 7, when Sister James and Father Flynn meet in the garden, the scene is bookended by a crow’s caw. Crows symbolize death, as they are scavengers, said to appear at a home shortly before someone passes, and to linger afterward. In this way, they are thought to guide souls into the afterlife. They also symbolize change: not just the change from life to death, but from one phase of life to another. For Sister James, the crow’s call represents her change from innocent and guileless to morally muddled. It is in this conversation that she confesses narrates her dream, in which her reflection is sheer darkness. Though she comes to profess her trust in Father Flynn in this act, it is clearly a choice to ignore her darker imaginings, which nonetheless will not leave her. 

Sister Veronica is mentioned in passing in the play as a nun who is going blind. Sister Aloysius wishes to protect her, asking Sister James to help her along if she seems to be struggling. In the Bible, blindness is used to describe people who are unable to receive divine revelation.