Religion, both Yoruba and Christian, is prominently featured in Black Sunday. Rotimi Abraham does not make an argument that one is better than the other; instead, the novel offers a view of the different types of religion that are part of Nigerian society. This theme first appears in Part 1, when Bibike mentions to Andrew and Peter a Yoruba prayer and the idea of heaven as she tells a story. Religion also holds a particularly prominent place in Ariyike’s life, which begins in the opening of the book with the start of her relationship with Pastor David, who returns as her husband later in the novel.

The “lived” aspect of this theme refers to the fact that the characters struggle with what religion means and how it manifests in their daily lives. This concept is primarily embodied in Ariyike, who develops her relationship with her faith throughout the novel. In the beginning, her idea of religion is twinged with youthful naivete, which is especially augmented by the fact that her parents have not yet left. She thinks: “I hoped that God could tell that my heart wanted him more than it wanted worldly music, or anything else.