In his introduction, Bunyan addresses his second book, known as Part II of The Pilgrim’s Progress. He orders the book to follow in the footsteps of Part I, embarking on a pilgrimage of its own. Bunyan calls the book by the name of Christiana and, thereby identifying it with Christian’s wife, Christiana.

Bunyan then imagines Christiana offering him several objections to the proposed pilgrimage. First, she disagrees that some may not believe that she is truly authored by the original writer of Christian’s tale. The author replies that Christiana needs only send for him, and he will arrive to claim her as his own creation. Second, Christiana says that some readers might react angrily to the book. Here Bunyan answers that she should not fear this, since the first book has so many readers across Europe and America. Third, Christiana objects that certain people might dislike the use of allegory. Bunyan defends using fiction to tell what he considers to be religious truths. Finally, Christiana asks about those readers who call Bunyan’s work mere romance, a style of heroic prose and verse narrative. Bunyan says that not everyone can be pleased but reminds Christiana of the long list of vibrant characters the book contains and reassures her that readers will love her.

The narrator recounts his follow-up dream about Christian’s wife and children left behind in the City of Destruction. This time he dreams of an elderly man named Sagacity, who visits to talk about the City of Destruction, and asks whether Sagacity has heard of Christian. Sagacity says that he has and that Christian resides now in the Celestial City. The narrator also asks Sagacity about Christian’s wife, Christiana, and their four sons. Sagacity answers that he knows they packed up and embarked on a journey to find Christian and be reunited. Sagacity now acts as a narrator and offers to tell the story of Christiana’s pilgrimage.

At the beginning of Sagacity’s tale, Christiana invites a fellow townsperson named Mercy to accompany her on the pilgrimage. She offers to hire Mercy as her servant but says that they will share all their possessions on the trip as equals. Mercy agrees, and Christiana is joyful, not only at having a caretaker for her four children on the journey but also at having urged another human toward salvation. Mercy feels pity for those whom she will leave behind. Christiana says that pity befits a pilgrim and that one day those left behind may choose to follow her.

Christiana, Mercy, and the children cross the Slough of Despond. They slip several times but do not fall in. At this point, the narrator says that Sagacity ends his tale, and the narrator himself falls asleep and follows Christiana’s progress in a dream. Christiana’s group comes upon the gate to the path that will lead them the rest of the way to the Celestial City. A frightening dog barks at them. A gatekeeper appears and demands to know who they are. Christiana says she is Christian’s wife, and the gatekeeper expresses admiration for him. He opens the gate and lets in Christiana and her children, but Mercy remains outside the gate. Terrified, she remembers a passage from the Gospel of Matthew in which two women are said to grind at a mill. According to the passage, only one is saved while the other is turned away. Mercy assumes she will be turned away but knocks on the door anyway. The gatekeeper demands to know who she is. Christiana explains. Mercy nearly faints from fear but is allowed in.

After passing through the gate, Christiana and Mercy express relief at having been admitted. Christiana remarks how odd it is that such an ugly and frightening dog should reside with the gatekeeper and asks the gatekeeper to explain. He says that the dog belongs to a neighbor and actually performs a useful service by barking so ferociously, scaring off beggars. By contrast, earnest pilgrims stand up to the dog. The gatekeeper feeds Christiana and her group and washes their feet.