In Chapter 17, Jonas spends an unscheduled holiday riding his bike along the river. The river becomes a metaphor that foreshadows Jonas's departure from the Community at the end of the novel:
Now, through the memories, he had seen oceans and mountain lakes and streams that gurgled through woods; and now he saw the familiar wide river beside the path differently. He saw all of the light and color and history it contained and carried in its slow-moving water; and he knew that there was an Elsewhere from which it came, and an Elsewhere to which it was going.
The river has always represented the danger beyond the borders of the Community. Children in the Community learn no clear distinction between "Elsewhere" as a vague place beyond the river and "Elsewhere" as the place old people eventually go when they are released. To leave the Community by crossing the river and to die are essentially the same thing. A little boy named Caleb drowns in the river before the start of the novel. Caleb's death in the waterways that lead "Elsewhere" reinforces the idea that exile and death alike are the end of meaningful existence. The river is something to be avoided.
Through his work with the Giver, Jonas has also come to see the river as a metaphor for life-giving connection. He realizes that there is an entire world "Elsewhere," beyond the Community's horizon, and that there is more than death to be found there. In a literal sense, to be caught in the river's current might be to drift toward "oceans and mountain lakes and streams that [gurgle] through the woods" like nothing Jonas has ever seen in real life. Jonas's memories of all these waterways are awash in "light and color and history." In a metaphorical sense, to jump in the river would be to jump into the current of history and human experience that runs through all these memories. Jonas is coming to see that avoiding the river may be safest, but it is also deeply isolating.
The way Jonas thinks of the river as a metaphor for connection foreshadows his choice to leave the Community at the end of the novel. Jonas's departure is not an abandonment, but rather an attempt to save his people. Their isolationism, both from history and the outside world, has led them to morally corrupt practices. The strongest example of this corruption is that they murder children who don't seem like they will be useful enough to justify their needs from society. Jonas believes that by crossing the river, he can turn it from a border into a waterway that reconnects the Community to "an Elsewhere from which it came, and an Elsewhere to which it" can go. In so doing, he hopes to restore the Community's underlying sense of humanity.
In Chapter 19, Jonas watches a recording of his father killing a baby and disposing of its body down a trash chute. The trash chute is a metaphor that emphasizes the shocking situational irony at play in this scene:
It seemed to be the same sort of chute into which trash was deposited at school.
His father loaded the carton containing the body into the chute and gave it a shove.
“Bye-bye, little guy,” Jonas heard his father say before he left the room. Then the screen went blank.
Jonas's father is a Nurturer. He was given this Assignment at 12 years old because of his natural talent as a caregiver. The Community has forgotten the feeling of love, but Jonas's father clearly feels something like love or at least devotion toward babies and young children. When Lily asks for her stuffed elephant, her mother tells her she is almost too old for it by Community rules. Her father, however, fetches it for her without a word. His soft spot for young children is what brings Gabriel into Jonas's life. Gabriel is on the path to be Released because he has greater-than-average care needs. Jonas's father applies for special permission to bring him home for a year to prepare him for adoption. This practice stretches the Community's rules. The family stretches the rules even more by naming Gabriel. Jonas's parents impress on him and Lily not to repeat the name outside the family, but Gabriel is more than a case number to all of them. They do not want him to be Released, even if the Community deems this outcome to be for the best.
It is not until Chapter 19 that Jonas realizes what fate truly hangs in the balance for Gabriel, and that the Community has been maintaining its stable population by way of eugenics and state-sanctioned murder. Jonas would be disturbed to see anyone killing a baby. However, his Nurturer father is perhaps the person he would least expect to harm a child. The situation is ironic as well as tragic: the citizen whose affection for babies has earned them the title of Nurturer should be protecting babies, not executing them for the simple crime of being the smaller of two twins. The trash chute evokes a metaphorical comparison between the baby and a piece of garbage. Jonas's father can go immediately from treating a child like the most precious thing in the world to killing it and tossing it in the trash. This metaphor reinforces the situational irony and helps Jonas see just how deeply the Community has damaged its citizens' sense of their own morality.
In Chapter 22, Jonas tries to use memories to help himself and Gabriel feel less hungry, but the sensation of starvation takes hold, a "gnawing, painful emptiness." This imagery gives way to a metaphor that stands at the heart of the book's message:
Jonas remembered, suddenly and grimly, the time in his childhood when he had been chastised for misusing a word. The word had been “starving.” You have never been starving, he had been told. You will never be starving.
Now he was. If he had stayed in the community, he would not be. [...]
But if he had stayed . . .
His thoughts continued. If he had stayed, he would have starved in other ways. He would have lived a life hungry for feelings, for color, for love.
For the first time in his life, Jonas understands on a sensory level the difference between hunger and starvation. Hunger is a desire for food, whereas starvation is an intense, unbearable need for food that can kill a person if it goes unmet. The Community boasts that it has solved the problem of starvation by carefully managing its population and food production, keeping them perfectly in balance. Jonas now knows that "population control" means eugenics and euthanasia for the most vulnerable. Others have had to die so that he would never feel true suffering. He sees now that his and others' lack of suffering has numbed them to the full human experience. Jonas's own father has killed children like Gabriel "for the greater good" because he is desensitized to the cruelty of such an act and believes it is worth the moral cost.
Jonas feels the "gnawing, painful emptiness" inside him and realizes that contrary to what he was once told, starvation was an apt metaphor all along for what he was experiencing in the Community. He did not know it, but he was starving for color when he had black-and-white vision. He was starving for love before he ever knew it existed. He was starving for deeper feelings when he was told he would never feel them. For generations, the Community has desperately needed the very things they have shunted aside in favor of Sameness. Maintaining Sameness is killing their spirits just as surely as starvation is killing Jonas's body.