Miss Lonelyhearts returns home to his austere one-room apartment, where he has nailed a figure of Christ to the wall. In bed, he reads a passage about universal love from Dostoevsky's novel The Brothers Karamazov. He considers the passage good advice and thinks that if he used it in his column, he would be successful and the world would be full of love. However, Shrike stands in the way. Miss Lonelyhearts recognizes that, though he has had a lifelong affinity with Christ, he has never allowed the "hysteria" of worship and faith to overcome him. He thinks of this hysteria as a snake whose mirrored scales bring the dead world to life, but when he chants "Christ" while looking at his figure, the snake uncoils in his mind and he stops and drifts off to sleep.
Miss Lonelyhearts dreams he is a magician who performs tricks with doorknobs. Afterward, he tries to pray with the audience, but he only recites a cynical prayer Shrike has taught him. The dream switches to Miss Lonelyhearts's college dorm, where he and two friends have just stopped their all-night argument over the existence of God to find some liquor. They buy some applejack near a farm and then, upon seeing lambs, decide to buy one to roast and eat. Miss Lonelyhearts wants to sacrifice the lamb to God first. They finally purchase the youngest lamb and march to a meadow. Miss Lonelyhearts chants "Christ" and tries to kill the lamb, but his two blows with a knife are inaccurate and damage the blade. The bloody lamb escapes. After a while, Miss Lonelyhearts pleads with his friends to put the lamb out of its misery, but they stay put. Miss Lonelyhearts finds the lamb and crushes its head with a stone and leaves its carcass to the flies.
Miss Lonelyhearts develops an obsession with imposing order on inanimate objects. Soon, however, the objects rebel, malfunctioning, breaking, getting lost. He finds the outside world is similarly chaotic. He thinks of someone named Betty who always seemed to provide order. By the time he arrives at her apartment across town, he is irritated, and her welcoming appearance does not lessen his confusion. Miss Lonelyhearts discovers that his tongue has turned into a "fat thumb," and tries to avoid speaking too much.
Inside the apartment, Miss Lonelyhearts surveys the surroundings and calls Betty "Betty the Buddha." He thinks about the fact that two months earlier she had accepted his marriage proposition, yet that he had guiltlessly avoided her thereafter. He feels Betty's breast inside her robe, and then, after she asks if he is sick, berates her for thinking anyone with a morality problem is sick. He says he has a Christ complex and loves humanity. She says she loves him, and he admits he loves her. She tells him to leave her alone, as he has made her feel bad.
West originally intended to open the novel with the "Lamb" section, as its graphic account of religion gone wrong sets the tone for the novel's overarching theme of religion's failure in the modern world. West foregrounds the lamb sacrifice by exposing the mere decorative function of Miss Lonelyhearts's figure of Christ—religion is only an ornament to festoon Miss Lonelyhearts's empty apartment walls. The sacrifice of the lamb itself is packed with meaning. The sacrificial lamb, an unblemished, innocent creature, is a clear symbol of Jesus in the Bible. Just as Jesus innocently died for man's sins, so does the lamb. Here, however, the sacrifice is obviously botched, demonstrating the failure of religion in the modern world—the lamb even lies in an ignoble state after its death, devoured by flies.
West's more subtle point is that Miss Lonelyhearts kills the animal not with the knife, as it should be done, but with a stone. Previously, in "Miss Lonelyhearts and the Dead Pan," Miss Lonelyhearts had not been able to find a target for his stone, which had stood both for false hope—as Shrike would have it, the stones being the platitudes Miss Lonelyhearts doles out in his column— and a sign of Miss Lonelyhearts's sin, as he did not throw the stone, possibly according to the Biblical dictum "Let he who is without sin cast the first stone." In his youth, however, Miss Lonelyhearts was able to cast the stone and put an end to the lamb's misery, so in a sense he was without sin. At the very least, Miss Lonelyhearts proves himself a merciful, sensitive college man. Still, he drinks illegally, and the fact that the liquor of choice is applejack gives the episode even more of a Biblical cant. Although Adam and Eve obviously preceded Jesus in the Bible, West shows the immediate corruption that comes from eating the apple of knowledge—the sacrifice fails. West links the end of the "Lamb" episode with the beginning of the "Fat Thumb" episode. The buzzing flies around the lamb's carcass are transformed into the chaotic modern world. In contrast to the start of the novel, in which the environment was sterile in its violence, the environment here is now rabid and murderous. As for the sin of drinking illegally, it is a kind of sin arbitrarily dictated by man, and Miss Lonelyhearts's religious devotion more than compensates for it.