Two themes that are clearly developed in this excerpt of "The Jilting of Granny Weatherall" are Granny's preoccupation with her own mortality and her unresolved feelings of abandonment from being left at the altar.
The theme of mortality is developed through Granny's interactions with Father Connolly. She is dismissive of his concerns about her soul, indicating that she feels comfortable with her own understanding of her relationship with God. She also reminisces about her life and feels secure in her beliefs that she has "a few favorite saints who cleared a straight road to God for her." These thoughts show that Granny is very preoccupied with her own mortality, especially as she ages and becomes more aware of her own mortality.
The theme of abandonment is developed through Granny's memories of being left at the altar. She recalls the wedding cake being thrown out and wasted, and the whole bottom of her world dropping out. She feels blind and sweating with nothing under her feet, and the walls falling away. Her sense of abandonment is also reflected in her request to "leave something to God" and not to lay a hand on the man who jilted her. This shows that despite the passage of time, Granny has never fully resolved her feelings of abandonment and betrayal.
Overall, Porter uses Granny's interactions with Father Connolly and her memories of being left at the altar to develop the themes of mortality and abandonment. These themes help to deepen the reader's understanding of Granny's character and her emotional state