Enemies indicts modern Judaism, which Singer regards as vulgar and materialistic without being real. Yadwiga, seeking to convert to Judaism, attempts to learn about the religion from her neighbors. From them she gets the impression that “the insurance policy and the dishwasher were both necessary aspects of Jewish observances.” Implied is Singer’s harsh condemnation of Jews who fail to perpetuate their heritage. Significantly, Masha thinks that she is pregnant but is merely suffering from nerves: She can produce only death, not life. Herman also dissociates himself from birth; he wants no children and does nothing to help Yadwiga through her pregnancy. It is she who says, “I want to have a Jewish child”—she who wants someone to say the memorial prayer for her.

Herman periodically attempts to reform. He puts on his skullcap and returns to the sacred books. During these intervals he is at peace with himself and the world; like Shifrah Puah, he finds consolation in religion. Yet his belief is not as strong as hers—he cannot remain faithful to tradition and so is ultimately lost.

Though Singer sees Jews tormenting themselves, he also sees them saving themselves. If some are their own worst enemies, some also show love. For a selfish Herman there is a generous Tamara; for the sterile Masha there is the fecund Yadwiga. With the birth of a new Masha at the end of the novel, Singer extends hope for a new and better generation. Perhaps this new Masha, safe from the Nazis, reared in a world of loving care, will carry on the tradition that her namesake and her father rejected.

Enemies deals with Holocaust survivors' readjustment to the mainstream of society. The Hitler era had left its imprint upon them and even when Herman, the main character, is given the opportunity to emigrate to America to start anew, he finds life too complicated to handle. As a husband to three women, he develops into a cheat, a swindler, and a liar. Family life and monogamy are lost virtues.

Like much of the Holocaust literature, Enemies wrestles with the idea that the Holocaust survivors are the perpetuators of Judaism, memorializing those obliterated by Hitler's savagery. Previously traditionalist, the main character begins to ponder the existence of God, especially in light of the Holocaust. Herman, now in America, struggling to find a new life, claims he does not know God and begins to turn away. He tries desperately to assimilate into American life; he marries a Gentile, keeps her hidden from society and drops out of community activities. His wife, Tamara, after witnessing man's inhumanity to man, turns to Communism, Zionism and feminism as a substitute for religion. As in many other works, Singer's characters contemplate a return to Judaism, but in Enemies, ironically, it is the Polish girl, who, after rescuing Herman from the Nazis and marrying him, converts to Judaism and brings up their child in the ways of his forefathers.

Imprisonment is another predominant theme. Herman, having been saved from extermination, traps himself to the point that there is no way out. Through a series of unlikely occurrences, Herman finds himself married to three women at the same time. Fearful of being exposed and jailed for bigamy, he tries to solve his problems only to discover that this time, unlike the Holocaust, there is no salvation, no escape.