In City of God, Doctorow’s underlying theme is humanity’s quest for meaning. Everett, the writer-narrator, is compiling a nonfiction account of the way his friend Pem (Thomas Pemberton) is dealing with loss of religious conviction. The son of a clergyman, Pem has repeatedly been disillusioned by his own ethical failures, especially his failure to discover a rational basis for Christian faith. He is considering a complete break with the church—a literal rejection of Christianity and a symbolic rejection of his father.

Then, a seemingly random street crime brings Pem into contact with Joshua Green, his wife Sarah Blumenthal, and their Synagogue of Evolutionary Judaism. A large brass cross stolen from the wall of St. Timothy’s is found on the synagogue’s roof. The cross seems symbolic of Pem’s diminished religious conviction: Beneath its brass veneer, it is steel, and it can easily be dismantled because it consists of two parts held together with screws. Pem never discovers the identity or motives of the thieves, but he sees the theft as a sign leading him to Joshua and Sarah, rabbis whose search for the City of God parallels his own. Complicating their quest, though, are stories of the Holocaust told by Sarah’s father, who is sinking into dementia. For Joshua especially, modern society seems overwhelmed by what St. Augustine called “the City of the World,” and he is martyred as he tries to reveal the ghetto horrors, thus ending humanity’s apparent indifference to the Holocaust.

Everett too becomes obsessed with the ghetto stories, which become the new focus of his book. Recording those stories brings him into closer contact with his own heritage, as he explores his father’s World War I exploits and those of his brother in World War II.

First Joshua and later Pem search for the long-lost ghetto records. In effect, Pem avenges his friend’s death by locating the trunk of records written by ghetto leaders, smuggled out by Sarah’s father and preserved by an anti-Nazi Roman Catholic priest. Sarah gives the originals to the government to be used as evidence against war criminals, and Everett uses her photocopies to complete his book.

Near the end of the novel is another symbolic film scenario. Obsessed with a war criminal living in the United States, a writer stalks the old man, considering ways to execute him, then accidentally kills him in a bike accident. Although the writer escapes capture, newspaper accounts portray him as the villain, and the old man is honored instead of dishonored. In contrast, even though the ghetto accounts are located too late to prosecute the local commandant, using contemporary accounts to authenticate his atrocities proves a more effective revenge.

As the novel ends, Pem converts to Judaism and, with Sarah, continues his quest to establish meaningful religious traditions. Soon they are married—a symbolic union of Jewish and Christian traditions prefigured early in the novel when Everett observes a great blue heron and a snowy white egret perched back to back, sharing a New York City pier. Near the novel’s end, another ecumenical symbol appears as Everett describes the City of Birds, near Madrid, where many species of birds peaceably pick over a huge garbage dump.