Eurycleia tells Penelope that Odysseus has finally come home and killed the suitors. The nurse mentions the telltale boar tusk scar on Odysseus's knee, but Penelope refuses to believe the story. She comes downstairs to speak to the stranger; he looks like Odysseus but also like the mysterious beggar. As she considers the stranger in indecision, Odysseus tells Telemachus that the palace must look as though they are celebrating a wedding; he wants to keep secret the fact that he has killed most of the high-born young men in Ithaca.
The scar is not proof enough for Penelope. Her suspicion is not cold-hearted, but just the opposite: she is so loyal to Odysseus that she fears betraying him in any way – even accidentally. To be loyal, she has to act disloyal at first; to love him, she has to act as though she doesn't love him. Disguise, to many of the characters, is a circuitous route to sincerity.
Athena changes Odysseus back into a handsome younger man. He chides Penelope for her cold welcome and tells the nurse that he will sleep alone. To test the stranger, Penelope tells Eurycleia to bring him the bridal bed, but Odysseus cries out angrily that the bed cannot be moved because he built it around an olive tree. The story is definite proof of his identity; Penelope cries and embraces him.
Penelope resists Odysseus because she fears that the gods want to trick her into disloyalty; if that were true, her reticence would be resistance to the will of the gods. In her small way, Penelope is choosing loyalty to her husband over piety, earthly honor over divine grace.
Odysseus warns Penelope that he must make one more long, dangerous journey before they can settle down in peace. According to the prophecy in Book 11, he must travel to a land far from any sea, plant an oar, and sacrifice animals to Poseidon. Finally they retire to bed. Before he leaves the following dawn, Odysseus tells Penelope to stay with her maids in her room, because men might come to avenge the suitors. He sets out with Telemachus, the swineherd, and the cowherd.
Now that he has restored honor to his household, Odysseus must make amends to Poseidon. Piety to the gods takes priority over his longing for family. In this, too, Odysseus shows great self-restraint: to protect his family from Poseidon's wrath, and therefore to benefit them in the long run, he must cause temporary pain to them and to himself.