A Book of Showings offers insights into sixteen visions that Julian of Norwich witnessed when lying in bed after falling seriously ill. Julian believes that the visions came from God, and she tries to explain the divine meaning of each in various chapters of the book.

Julian's visions help her discover the true purpose of God. In one, Julian holds a hazelnut in her hand and realizes three important things: God created the seed, He loved it, and He allowed it to exist. Therefore, human beings should be grateful to God for their existence. Julian also states that suffering is normal and God will always be there to rescue his people.

Julian finishes the book by telling her readers not to worry about their sins: all, she says, will be well.