Mrs. Dempster's presence is one of the most overwhelming factors that influence Dunstan's feeling of rebirth. On the battlefield in World War I, Dunstan suffers a rather horrific accident with shrapnel. As he is huddled in a shattered remain of a building with shattered remains of a body, he sees Mrs. Dempster's face in a religious statue. His period of unconsciousness that follows helps him to believe that Mrs. Dempster is a saint that miraculously gave herself in order to facilitate his recovery.
It is for this that he is able to feel that he has been "reborn." Dunstan understands that his injury from the war should have left killed. He also recognizes that the war took so many lives that, in all probability, his life should have been taken, as well. In seeing Mrs. Dempster's face projected on a religious statue, being lulled into a state of unconsciousness and reflecting on the beatific moment he experience, Dunstan feels reborn. It is for this reason that he commits himself to the exploration of saints in the modern condition.