The History of Monotheism
Most people meet the Abrahamic religions — Judaism, Christianity, and Islam — as three fixed, monotheistic faiths. Their shared belief in one God, however, developed over centuries: most scholars trace it from Canaanite polytheism through an intermediate stage of monolatry (worshipping one god while granting that others exist) to a decisive exilic turn around 540 BCE.
The earliest layers of the Hebrew Bible assume a populated heavens. The first commandment — "You shall have no other gods before me" (Exodus 20:3) — forbids the worship of other gods without denying that they exist. Deuteronomy 32:8-9 pictures a high god apportioning the nations among divine beings, with YHWH receiving Israel as his allotment. Psalm 82 opens with God standing in a divine council, passing judgment on other gods. This is monolatry, not monotheism — and it was the ordinary religious world of ancient Israel.
The vocabulary matters here. Polytheism is the worship of many gods. Monolatry is the worship of one god while conceding that others are real. Henotheism is devotion to a single god without ruling on the rest. Monotheism is the claim that only one God exists at all. Israelite religion moved across these categories over centuries, not in a single leap.
Mark S. Smith, in The Early History of God (2001), traced how YHWH began as one deity among many in the Canaanite pantheon, gradually absorbing the roles and titles of the high god El and the storm god Baal as Israelite religion consolidated. The God of the later biblical writers is, in part, a convergence of several earlier divine figures.
The turn to strict monotheism accelerated under catastrophe. When Babylon destroyed the Jerusalem temple in 586 BCE and deported Judah's elite, the theological stakes were stark: if YHWH was Israel's God and Israel lay in ruins, had YHWH been beaten?
Second Isaiah answered by raising the stakes rather than lowering them. The anonymous exilic author of Isaiah 40-55 declared that YHWH had not lost — YHWH was the only God, and Babylon's gods were nothing. "Before me no god was formed, nor shall there be one after me" (Isaiah 43:10). "I am the LORD, and there is no other; besides me there is no god" (Isaiah 45:5). These are not the words of monolatry. They are explicit denials that any other god exists — the first unambiguous monotheism in the Hebrew Bible, composed around 540 BCE, in the Exilic period.
The defeat became the proof.
If YHWH alone governs history, then the fall of Jerusalem was not evidence of divine weakness but of divine sovereignty — a judgment the one God had chosen to enact. The crisis of national destruction became the catalyst for a theological breakthrough.
Israel was not the first to experiment with exclusive worship. Six centuries earlier, the Egyptian pharaoh Akhenaten (reigned ~1353-1336 BCE) elevated the sun-disk Aten above all other gods and suppressed their cults — the earliest documented attempt at worshipping one deity alone. Jan Assmann, in The Price of Monotheism (English translation 2010), called this the first "counter-religion," a system that defines itself against all other worship. But Akhenaten's reform died with him; traditional Egyptian religion was restored within a generation. Most scholars see no direct line from Amarna to Israel — the parallel shows instead that royal decree alone could not make exclusive worship last.
The monotheism that endured grew from community practice, textual tradition, and argument. Exilic and post-exilic editors did more than proclaim the new theology; they read it back into older texts, reframing narratives that once reflected a crowded heavens. The final form of the Torah carries the marks of that editing — one reason the question of who wrote the Bible is layered rather than simple.
The Monotheistic Religions Compared
The strict monotheism that crystallized in the exile became the seedbed for the world's major monotheistic religions — but not every monotheistic tradition descends from it. Six are usually counted: three Abrahamic, and three that developed on their own tracks.
| Tradition | Emerged | Name / concept of God | Central text | Abrahamic? |
|---|---|---|---|---|
| Judaism | Israelite religion; strict monotheism by ~540 BCE | YHWH; oneness declared in the Shema | Tanakh (Hebrew Bible) | Yes |
| Christianity | 1st century CE | One God in three persons (the Trinity) | Old and New Testaments | Yes |
| Islam | 7th century CE | Allah; absolute oneness (tawhid) | Quran | Yes |
| Zoroastrianism | Ancient Persia; dates debated (2nd millennium–6th c. BCE) | Ahura Mazda, opposed by Angra Mainyu | Avesta | No |
| Sikhism | Punjab, late 15th century CE | One formless universal God (Ik Onkar) | Guru Granth Sahib | No |
| Baha'i Faith | Persia, 19th century CE | One God revealed progressively | Writings of Baha'u'llah | No |
Each Abrahamic tradition draws the boundary of "one God" differently, and the differences have divided them for centuries.
Judaism anchors its monotheism in the Shema (Deuteronomy 6:4): "Hear, O Israel: the LORD our God, the LORD is one." The Hebrew echad ("one") asserts an indivisible singularity, later formalized by the medieval philosopher Maimonides as the second of his thirteen principles of faith.
Christianity affirms one God while confessing Father, Son, and Holy Spirit — the doctrine of the Trinity, worked out across the fourth century and defined at the Council of Nicaea in 325 CE and the Council of Constantinople in 381 CE. Judaism and Islam both regard this as a departure from strict oneness; Christian theology holds that three persons share one divine substance.
Islam defines oneness through tawhid, the absolute indivisibility of God (Allah). Sura 112 states it flatly: "He neither begets nor is begotten, nor is there any equivalent to Him" — a rejection of both Arabian polytheism and, on the Islamic reading, the Trinity, which Islamic theology classes as shirk (associating partners with God).
The three non-Abrahamic monotheisms developed independently. Zoroastrianism, founded by the prophet Zarathustra in ancient Persia, centers on Ahura Mazda, the god of truth and light; scholars still debate whether its earliest form was fully monotheistic or dualistic. Its importance for the Abrahamic story is one of proximity: when Cyrus of Persia conquered Babylon in 539 BCE and let the Judean exiles return, Israelite thinkers met Persian ideas at a formative moment — Second Isaiah even calls Cyrus God's "anointed" (Isaiah 45:1). Karen Armstrong, in A History of God (1993), traced possible Persian influence on Jewish notions of angels, resurrection, and final judgment, while noting that direct borrowing is hard to demonstrate.
Sikhism, founded by Guru Nanak in late-15th-century Punjab, affirms one formless God (Ik Onkar) and grounds its monotheism in the Guru Granth Sahib. The Baha'i Faith, emerging from 19th-century Persia, teaches one God disclosed through a succession of prophets — including Abraham, Moses, Jesus, Muhammad, and Baha'u'llah. Reza Aslan, in God: A Human History (2017), argued that exclusive devotion to one deity tends to surface during periods of political consolidation, when a single ruler's authority mirrors a single god's sovereignty.
The tally of "six" is a convention rather than a fixed rule — some scholars fold in smaller traditions, and each of the six contains internal movements that define oneness in their own way. Islam, notably, does not regard itself as a later development at all: it understands its message as the original monotheism of Abraham restored. Each tradition tends to tell the history of monotheism with itself at the center — part of what makes studying that history as a historical question, rather than a theological verdict, so productive.
The Three Abrahamic Religions: One Abraham
The three Abrahamic religions — Judaism, Christianity, and Islam — trace their origins to Abraham, a patriarch each tradition claims as a foundational ancestor. Between them they account for more than half the world's population, and all three inherited the strict monotheism that crystallized in Israel.
The relationship among them is not a single trunk with three clean branches. It is a centuries-long entanglement of shared texts, competing interpretations, and divergent theology — three traditions built from overlapping source material. All three treat Abraham as central. All three preserve narratives of creation, flood, Moses, and covenant that carry recognizable literary DNA. And all three, at times, retell the same story to make pointedly different theological arguments.
What connects them is not only a shared ancestor but a shared textual environment. The Torah, the Christian Bible, and the Quran do not merely name the same figures — they engage the same stories, sometimes in ways that expose sharp disagreement beneath the surface of apparent agreement.
| Figure / Story / Concept | Torah / Hebrew Bible | Christian Bible | Quran |
|---|---|---|---|
| Abraham (Ibrahim) | Patriarch of Israel; covenant with God (Genesis 12-25) | Patriarch; model of faith (Romans 4, Galatians 3) | Prophet and builder of the Kaaba; submitted to God's will (Sura 2, 14, 37) |
| Moses (Musa) | Lawgiver; led Israel from Egypt; received Torah at Sinai (Exodus-Deuteronomy) | Lawgiver; foreshadows Christ (Acts 7, Hebrews 3) | Prophet sent to Pharaoh; received the Tawrat (Sura 2, 7, 20, 28) |
| Jesus (Isa) | Not present | Son of God; crucified and resurrected; central figure of faith (Gospels, Paul's letters) | Prophet and messiah born of a virgin; not crucified; not divine (Sura 3, 4, 5, 19) |
| Mary (Maryam) | Not present | Mother of Jesus; virgin birth (Matthew 1, Luke 1-2) | Mother of Isa; an entire sura bears her name (Sura 19); most-named woman in the Quran |
| Creation narrative | Two accounts: Genesis 1 (six days) and Genesis 2 (garden of Eden) | Inherits Hebrew Bible accounts; creation theology in John 1, Colossians 1 | God created heavens and earth in six periods; no garden temptation sequence as in Genesis (Sura 7, 11, 41) |
| Flood narrative | Noah and the ark; global flood; covenant with rainbow (Genesis 6-9) | Noah as model of faith and warning (Matthew 24, 1 Peter 3, 2 Peter 2) | Nuh sent to his people; local flood; his son drowned (Sura 11, 71) |
| Adam and Eve | First humans; garden, serpent, exile (Genesis 2-3) | Adam as type of Christ; fall and redemption (Romans 5, 1 Corinthians 15) | Adam and his wife both err; both repent; no doctrine of original sin (Sura 2, 7, 20) |
The pattern holds across the table: three traditions share narrative raw material, and each fits it into a different theological architecture.
The Hebrew Bible's Adam and Eve ground a story of exile and covenant. Paul reads it as the fall that makes Christ's redemption necessary (Romans 5). The Quran tells it without original sin — Adam errs, repents, and is forgiven. Same characters, different theology — and that gap is where the comparison begins.
Scripture Across Traditions
The scriptures of Judaism, Christianity, and Islam are not three separate libraries that happen to share a shelf. They are texts in active conversation — sometimes explicit, sometimes implicit — with one another and with a common body of earlier material.
The closest relationship runs between the Hebrew Bible and the Christian Old Testament. How the Old Testament relates to the Torah is subtler than it first appears: the Christian Old Testament contains the same core texts as the Jewish Tanakh but arranges them differently, and Catholic and Orthodox canons add books that Protestant and Jewish canons exclude. The texts are largely the same; the anthology is not.
The Quran's relationship to the Bible is different in kind. It does not reproduce biblical narratives verbatim — it alludes to them, retells them in compressed or reframed form, and often assumes its audience already knows the earlier version. Figures like Abraham, Moses, Joseph, and David appear in both, but with different emphases, dialogue, and framing. The question of whether the Quran is older than the Bible has a clear chronological answer — the Hebrew Bible's earliest texts predate it by well over a millennium — even though the Quran understands itself to confirm and correct earlier revelation rather than to follow it.
The figure of Jesus in the Quran shows how far the same person can travel between traditions. The Quran affirms Jesus as a prophet, as messiah, and as virgin-born — while explicitly denying his crucifixion and his divinity. These are not marginal disagreements but distinct theological structures built on shared material.
Later texts extend the pattern. The Book of Mormon's relationship to the Bible is a 19th-century instance of the same phenomenon — a new scripture claiming continuity with the biblical tradition while adding its own narrative frame and theological claims. The longer arc of how these collections were assembled and canonized runs through the history of Christianity and the debates over who decided what belongs in the Bible.
Before the Bible: Ancient Near Eastern Roots
The literary traditions behind the Hebrew Bible did not emerge in isolation. Creation narratives, flood stories, divine councils, and law codes circulated across Mesopotamia, Egypt, and the Levant for millennia before the earliest biblical texts were composed. The biblical authors knew this material. So did their first audiences.
The relationship between the Enuma Elish and Genesis is among the most studied examples. The Enuma Elish, a Babylonian creation epic dating to at least the 12th century BCE, tells how the god Marduk defeats the chaos-monster Tiamat and shapes the world from her body. Genesis 1 describes God ordering a formless deep — and the Hebrew word for that deep, tehom, is linguistically related to the Akkadian Tiamat. Hermann Gunkel first mapped these connections in 1895, and the scholarly conversation has continued ever since.
The relationship is not simple borrowing. It is a shared cultural vocabulary that different authors bent toward different theological ends. The Atrahasis epic, composed around 1700 BCE, carries a flood narrative with striking structural parallels to Genesis — divine decision, a single righteous survivor, a boat, birds sent out, a sacrifice afterward. The Gilgamesh epic shares even more specific detail. All were circulating centuries before the biblical versions reached their present form.
The Genesis authors were composing within a rich literary environment, and their choices about what to keep, change, and reframe reveal their priorities with unusual clarity. The ancient Near Eastern context makes the biblical texts more legible, not less.