The tone of Uncle Tom's Cabin is formal, religious, and zealous. A fervent believer in Christianity, Beecher Stowe believed the institution of slavery was incompatible with the Christian faith, and she penned the novel with the explicit purpose of convincing a Christian audience of slavery's ills. In this way, she uses Christianity as the novel's moral framework; as a result, the narrator frequently alludes to God and the Bible, offering judgements on what is good and what is evil. Beecher Stowe wanted to draw her audience's attention to how slavery corrupted everyone involved, which would in turn hopefully convince them to support ending the practice.
The Bible is also a motif, or recurring element, in the novel. The text becomes a source of solace and hope for Uncle Tom and eventually symbolizes his reverence for God. Religious characters like the Quakers (who shelter runaway slaves), Uncle Tom, and Eva St. Clare are depicted in the novel as morally good, while those who are unfaithful or even hateful of religion—like the cruel master Simon Legree—are characterized as evil. As a result, the novel has a moralistic tone that clarifies Beecher Stowe's beliefs, drawing on religion to set forth an abolitionist message.