12.4 — Judaism, Christianity, Islam: The Shared Root and the Real Differences

Three traditions, roughly 3.9 billion people between them, all tracing to the same figure and the same claim.

And the differences between them are frequently described by their partisans and almost never described neutrally, so this chapter does that.

The shared root

All three trace to Abraham, and all three make the same fundamental claim: there is one God, who is personal, who acts in history, and who has made demands of human beings.

And that claim is genuinely distinctive. Compare Part 11: most traditions have many gods, or an impersonal principle, or a divine that is identical with the world. A single, personal, moral God who intervenes in history and issues commands is a specific and unusual position.

They also share: a linear rather than cyclical view of time, a final judgement, prophecy as a category, and scripture as central.

Judaism

The oldest, and the smallest — around 15 million people.

The central claim is not primarily about belief. It is covenant: an agreement between God and a specific people, with obligations on both sides.

And what follows from that shapes everything.

The obligations are detailed and practical. The tradition counts 613 commandments in the Torah, covering diet, agriculture, law, worship, family, business and the treatment of strangers.

And the intellectual life is legal. The Talmud — the record of centuries of rabbinic debate on how to apply the law — is enormous, and its characteristic feature is that it preserves the losing arguments. A page of Talmud typically has a text in the centre and layers of commentary and counter-commentary around it, from different centuries, disagreeing.

It is a tradition organised around argument rather than around creed, and it has no equivalent of a church hierarchy or a doctrinal authority.

No missionary activity. Conversion is possible and is traditionally discouraged rather than sought.

And on the afterlife: strikingly little. The Hebrew Bible says almost nothing about it. The tradition's focus is on this life and on this world, and the later development of ideas about a world to come is genuinely later.

And a note that belongs here: the history of Jewish communities in Christian and Muslim societies is a history of periodic expulsion, forced conversion, massacre and legal disability, culminating in the industrialised murder of six million people in the twentieth century. Volume VIII covers it. No account of these three traditions is honest without it.

Christianity

The largest, around 2.4 billion.

A movement inside first-century Judaism that became a separate religion.

The central claim is a specific historical and theological one: that Jesus of Nazareth was the promised messiah, that he was God incarnate, that he was executed by Roman authority, and that he rose from the dead — and that this event fundamentally changed the human relationship with God.

And the consequences of that shape everything.

It is belief-organised (12.1). Because the claim is a proposition about a specific person, holding the proposition is what membership means, and this is why Christianity produced creeds, councils, heresies and doctrinal splits on a scale the other two did not.

The law is superseded. Paul's argument — that gentile converts need not adopt Jewish law — is what made it a universal religion rather than a Jewish sect, and it is the most consequential decision in the tradition's history.

Salvation is by grace rather than by works, in most formulations, with a long argument about the relationship between the two which produced the Reformation.

And the Trinity: one God in three persons. This is genuinely difficult, was hammered out over four centuries of councils and disputes, and is the point at which the other two traditions object most strongly.

The main divisions: Orthodox, Catholic and Protestant, split in 1054 and in the sixteenth century respectively, and Protestantism has since divided repeatedly.

Islam

Around 1.9 billion, and the youngest of the three.

The central claim: God is absolutely one, indivisible, and has no partners or offspring; Muhammad is the last in a line of prophets that includes Abraham, Moses and Jesus; and the Quran is God's direct speech, revealed to him.

And each of those is doing specific work.

Tawhid, the oneness of God, is the foundation and it is uncompromising. The gravest error in Islam is shirk — associating anything with God — and this is precisely why the Trinity and the divinity of Jesus are rejected. Jesus is honoured as a prophet and a messiah; his divinity is not accepted.

The Quran is not analogous to the Bible. It is understood as God's own uncreated speech, in Arabic, which is why translation is regarded as interpretation rather than as the thing itself, and why memorisation of the whole text is a widespread practice.

And the practice is specified. The five pillars: the declaration of faith, prayer five times daily, charity as a fixed proportion of wealth, fasting during Ramadan, and pilgrimage to Mecca once if able.

It is practice-organised more than Christianity and belief-organised more than Judaism, and it has no priesthood — scholars have authority through learning, not through ordination.

And it includes a legal tradition, sharia, developed in schools of jurisprudence with substantial internal disagreement — a fact that is regularly lost in discussions of it.

The main division: Sunni and Shia, originating in a seventh-century dispute over succession after Muhammad's death, which developed into distinct legal and theological traditions.

The real differences

Now the comparison, stated as neutrally as it can be.

On God's nature. Judaism: absolutely one, and covenanted with a people. Christianity: one in three persons, and incarnate. Islam: absolutely one, and utterly transcendent.

On Jesus. A first-century Jewish teacher, not the messiah (Judaism). God incarnate, risen (Christianity). A great prophet, born of a virgin, not divine, not crucified in most interpretations (Islam).

On scripture. A text requiring interpretation through an ongoing legal tradition (Judaism). Inspired, with the interpretive authority varying by denomination (Christianity). God's direct and uncreated speech (Islam).

On what is required. Observance of the covenant's obligations. Faith in Christ. Submission to God, expressed in the five pillars.

On who it is for. A specific people, with conversion possible and not sought. Everybody, and actively sought. Everybody, and actively sought.

And on the afterlife. Comparatively little emphasis. Central. Central.

What they share ethically

And the overlap here is much larger than the doctrinal overlap, which is 12.9's general finding.

All three: one God, moral demands, care for the poor as an obligation rather than a virtue, prohibitions on murder, theft, adultery and false witness, honour to parents, and a day or period set aside.

All three have a version of the golden rule.

All three have a strong tradition of hospitality to strangers.

And all three developed sophisticated mystical traditions that resemble each other far more than the mainstreams do — Kabbalah, Christian mysticism, and Sufism — and the mystics of all three were regarded with suspicion by their own institutions, which is a pattern worth noticing.

What is worth being honest about

Three things.

The traditions have persecuted each other and their own dissenters, extensively, and 12.8 is the chapter for it.

The differences are real and are not dissolvable by goodwill. Whether Jesus was God is not a matter of emphasis. A conversation that pretends the three traditions agree is not respecting any of them.

And the shared root is genuine. They read overlapping scriptures, revere overlapping figures, and make the same fundamental claim about the kind of thing God is. Which is exactly why the disputes have been so bitter — the conflicts between them have generally been sharper than their conflicts with traditions they have nothing in common with.

Proximity is what produces this, and 8.9 said the same about envy: you do not fight across a gap you cannot imagine crossing.

What to carry from this page

Covenant, incarnation, submission. Three words for the three central relationships, and most of the differences follow from which one is at the centre.

Judaism preserves the losing arguments on the same page as the winning ones. That is a remarkable intellectual norm and it is worth borrowing.

The Quran is understood as God's direct speech rather than as an inspired text, which is why the relationship to translation is completely different from the Christian one.

And the mystics of all three resemble each other more than the mainstreams do, and were all viewed with suspicion by their own institutions. That is one of the most interesting facts in comparative religion and 12.9 takes it up.

Next: 12.5 — four smaller traditions, each of which solved a problem the large ones did not.