A group of believers from the soldiers of the Caliphate .  .  . set out targeting the capital of prostitution and vice, the lead carrier of the cross in Europe—Paris." Thus did the Islamic State claim credit for its terror spree in the City of Light in November, the latest in a string of murderous attacks fueled by Islam. The jihadists, naturally, observe their violent struggle against the crusading West through a Koranic lens, insistent that their texts and traditions demand no less. But will this tendency ever change? Possibly, assuming that the past is prologue. "Christianity," Heinrich Heine observed nearly two centuries ago, "has somewhat mitigated that brutal German love of war, but it could not destroy it."

Exactly how religion both foments and tempers violence has bedeviled theologians, historians, and statesmen for centuries. Now, Lord Jonathan Sacks capably wrestles with this vexing question, explores its origins in biblical sibling rivalries, and presents a creative way of reframing it—along the way offering a hopeful, if not entirely realistic, pathway to peace.

The former chief rabbi of the United Kingdom and author of more than 20 books, Sacks begins with some necessary brush-clearing, including the fantasy that Islamist violence is unmoored from faith: "When terrorist or military groups invoke holy war, define their battle as a struggle against Satan, condemn unbelievers to death and commit murder while declaring 'God is great,' " he writes, "to deny that they are acting on religious motives is absurd." At the same time, Sacks rightly observes that only a fraction of global violence can be attributed to religion. Even enlightened thinkers, from Kant to Hegel to Fichte to Schopenhauer, derided Jews as "vampires," "scum of the earth"—and worse. "Philosophical antisemitism from Voltaire to Heidegger," Sacks reminds us, "is a little-known phenomenon but a devastating one."

Instead, he contends, "violence has nothing to do with religion as such. It has to do with identity and life in groups." Religion "links people, emotionally, behaviorally, intellectually, and spiritually into communion and thus community. .  .  . Within groups we practice altruism. Between them we practice aggression." Ground zero for such intergroup aggression is antisemitism, "the first warning signal of a world order in danger of collapse. .  .  . Wherever you find obsessive, irrational, murderous antisemitism, there you will find a culture so internally split and fractured that if its members stopped killing Jews, they would start killing one another."

Not surprisingly, such intragroup violence is most plainly showcased in the abattoir of the Levant, where Sunni and Shia slaughter each other mercilessly. But crucially, Sacks traces most forms of religious conflict to the fierce sibling rivalries recited in the Bible; Islam and Christianity reenacting the struggle between Isaac and Ishmael, Christianity and Judaism reliving the battle of Esau and Jacob.

Paul and the early Church Fathers seized the mantle of Jacob, painting un-Christianized Jews as benighted Esaus while, through the Koran, Mohammed and his followers reimagined Ishmael as the favored son while relegating Jews and Christians to the overlooked Isaac. "Sibling rivalry," Sacks notes, "plays a central role in human conflict, and it begins with .  .  . the desire to have what your brother has," be it a birthright, a parent's love, or God's favor.

Yet, he queries, what if these depictions of such intense intrafamily cruelty contain beneath the surface "a second level of meaning" urging us to recognize that "violence in a sacred cause is not holy but an act of desecration?" He then boldly reframes the stories of the unfavored sons Ishmael (whom Abraham loves and blesses and does not forsake), Esau (who receives ample material blessings while his younger brother attains spiritual ones), and Joseph's brothers (who repent their sin of hatred when the brother they sold into slavery, now in charge in Egypt, mock-imprisons them to play-act a role reversal)—all of which end "on a note of reconciliation, each time at a more profound level."

This role reversal is crucial to interdenominational understanding. In Sacks's view, "the message of Genesis is that love is necessary but not sufficient. You also need sensitivity to those who feel unloved. .  .  . The way we learn not to commit evil is to experience an event from the perspective of the victim." Specifically, he writes, "the best way of curing antisemitism is to get people to experience what it feels like to be a Jew." More broadly, Sacks asserts faith not only licenses but mandates a perspective change. He casts the Bible itself as "God's reply to those who commit violence in his name. God does not prove his love for some by hating others. Neither, if we follow him, may we."

Sacks's footing is firmest when he's interpreting biblical texts and deriving ethical lessons from them; he paints the vivid characters populating Genesis with unrivaled poise, passion, and sensitivity. His language sparkles, too, when outlining the trajectory of Jewish history in its biblical and rabbinic eras, from its bellicose origins to its quietist present and equally so when exploring Christianity's similar evolution.

Sacks is less persuasive, however, when explaining how that transformation can be replicated today, especially by Islam. For instance, in describing how the Jews sublimated their injunction to destroy the biblical nation of Amalek into a metaphor for pure evil, both internal and external, as a "struggle within the soul," Sacks suggests how Islamists might reinterpret jihad. But are they listening? Should they be? After all, while Muslims theoretically hold the Bible in high regard, they're not bound by its teachings, let alone by a contemporary rabbi's reinterpretation. That the Jews have largely renounced violence hardly means Islamists will do the same.

If this book has a flaw, it's this: It ought to appeal to all good-hearted religious people. However, the bad-hearted religious people don't seem to be listening and the good-hearted secular folks don't really need to. Sacks concludes by urging "an international campaign against the teaching and preaching of hate," insisting on "reciprocal altruism" and recognizing that "we are all children of Abraham." Will his call be enough to turn the tide of religious violence? Probably not. Must we heed it anyway? Absolutely.

Michael M. Rosen is an attorney and writer living in Israel.