The crucifix
In possession novels, the crucifix is used to ward off evil and demonic spirits. In The Case Against Satan, Bishop Crimmings holds a crucifix on Susan's arm and it begins to burn into her skin, which suggests she is possessed by a demonic spirit. However, this is later thrown into doubt by Sargent, who privately concludes that Susan is not possessed, but is mentally disturbed. Sargent's search to find the truth is a key aspect of this novel.
Susan's nakedness
In the novel, Susan strips naked in front of Gregory, which represents her disturbed mental state and behavior. The act also represents her crudeness, corruption and impurity in the eyes of her father and the community and is used as evidence that she is possessed. Her nakedness also represents her vulnerability.
At the beginning of the text, Gregory associates Susan’s behavior with repressed sexuality, saying that disturbances “in young women… were so often rooted in sexual hysteria". He believes her disturbance is due to repressed sexuality.
Corruption
The idea of corruption is a key motif in the text. Corruption is found at the heart of the family home when it is revealed that Susan is abused by her father. The Church as an establishment is also shown to have abuse and corruption at its center. Finally, the text also concludes that there is darkness and corruption in every human. Sargent concludes privately that this is the true cause of Susan's action, rather than demonic possession.
Religious buildings
Much of the novel’s action takes place in religious buildings, such as the church and rectory. The settings are symbolic as a place of God, spirituality, and faith. Interestingly, the rectory is where Susan’s exorcism takes place. This is significant, as it is symbolic of underlying darkness in the church, which is represented by Susan’s corruption and vulgarity. The space is therefore symbolic of purity and goodness, but also of corruption and evil.
Gregory has a bad first impression of the rectory, which hints that something is amiss. He “looked about with distaste at the parlor of his new rectory. He took in the scattering of vases and ash trays and dollies, its aggressively middle-class wallpaper, its bad holy pictures, its obtrusive pillars of dark wood."
