Jews, Christians and Muslims all believe in a single, omnipotent deity that created the heavens and earth. But if he was and is the only god, why would God need a name?

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The Bible explicitly tells us that God has one, which indicates he had to be distinguished from other celestial beings, just like humans use names to identify different people.

What that name might be is another matter. The Jewish prohibition on speaking God’s name means that its correct pronunciation has been lost. All we know is that the Hebrew Bible spells it out as four consonants known as the Tetragrammaton – from the Greek for “four letters,” which are transliterated as Y-H-W-H.

The existence of a proper name for God is the first indication that the history of Yhwh and his worship by the Jews is a lot more complicated than many realize.

In gods we trusted

Modern biblical scholarship and archaeological discoveries in and around Israel show that the ancient Israelites did not always believe in a single, universal god. In fact, monotheism is a relatively recent concept, even amongst the People of the Book.

Decades of research into the birth and evolution of the Yhwh cult are summarized in “The Invention of God,” a recent book by Thomas Römer, a world-renowned expert in the Hebrew Bible and professor at the College de France and the University of Lausanne. Römer, who held a series of conferences at Tel Aviv University last month, spoke to Haaretz about the subject.

The main source for investigating the history of God is, of course, the Bible itself.

When exactly the Jewish holy text reached its final form is unknown. Many scholars believe this happened sometime between the Babylonian exile, which began after the fall of Jerusalem in 587 BCE (some 2600 years ago), and the subsequent periods of Persian and Hellenistic rule.

However, the redactors of the Bible were evidently working off older traditions, Römer says.

“Biblical texts are not direct historical sources. They reflect the ideas, the ideologies of their authors and of course of the historical context in which they were written,” Römer explains.

Still, he notes, “you can have memories of a distant past, sometimes in a very confusing way or in a very oriented way. But I think we can, and we must, use the biblical text not just as fictional texts but as texts that can tell us stories about the origins.”

What’s in God’s name

The first clue that the ancient Israelites worshipped gods other than the deity known as Yhwh lies in their very name. “Israel” is a theophoric name going back at least 3200 years, which includes and invokes the name of a protective deity.

Going by the name, the main god of the ancient Israelites was not Yhwh, but El, the chief deity in the Canaanite pantheon, who was worshipped throughout the Levant.

In other words, the name “Israel” is probably older than the veneration of Yhwh by this group called Israel, Römer says. “The first tutelary deity they were worshipping was El, otherwise their name would have been Israyahu.”

The Bible appears to address this early worship of El in Exodus 6:3, when God tells Moses that he “appeared to Abraham, Isaac and Jacob as El Shaddai (today translated as “God Almighty”) but was not known to them by my name Yhwh.”

In fact, it seems that the ancient Israelites weren’t even the first to worship Yhwh – they seem to have adopted Him from a mysterious, unknown tribe that lived somewhere in the deserts of the southern Levant and Arabia.

The god of the southern deserts

The first mention of the Israelite tribe itself is a victory stele erected around 1210 BCE by the pharaoh Mernetpah (sometimes called “the Israel stele”). These Israelites are described as a people inhabiting Canaan.

So how did this group of Canaanite El-worshippers come in contact with the cult of Yhwh?

The Bible is quite explicit about the geographical roots of the Yhwh deity, repeatedly linking his presence to the mountainous wilderness and the deserts of the southern Levant. Judges 5:4 says that Yhwh “went forth from Seir” and “marched out of the field of Edom.” Habbakuk 3:3 tells us that “God came from Teman,” specifically from Mount Paran.

All these regions and locations can be identified with the territory that ranges from the Sinai and Negev to northern Arabia.

Yhwh’s penchant for appearing in the biblical narrative on top of mountains and accompanied by dark clouds and thunder, are also typical attributes of a deity originating in the wilderness, possibly a god of storms and fertility.

Support for the theory that Yhwh originated in the deserts of Israel and Arabia can be found in Egyptian texts from the late second millennium, which list different tribes of nomads collectively called “Shasu” that populated this vast desert region.

One of these groups, which inhabits the Negev, is identified as the “Shasu Yhw(h).” This suggests that this group of nomads may have been the first to have the god of the Jews as its tutelary deity.

“It is profoundly difficult to sort through the haze of later layers in the Bible, but insofar as we can, this remains the most plausible hypothesis for the encounter of Israelites with the Yhwh cult,” says David Carr, professor of Old Testament at Union Theological Seminary in New York City.

The many faces of god

How exactly the Shasu merged with the Israelites or introduced them to the cult of Yhwh is not known, but by the early centuries of the first millennium, he was clearly being worshipped in both the northern kingdom of Israel and its smaller, southern neighbor, the kingdom of Judah.

His name appears for the first time outside the Bible nearly 400 years after Merneptah, in the 9th-century BCE stele of Mesha, a Moabite king who boasts of defeating the king of Israel and “taking the vessels of Yhwh.”

While Yhwh’s cult was certainly important in the early First Temple period, it was not exclusive.

“Jeremiah speaks about the many gods of Judah, which are as numerous as the streets of a town. There was certainly worship a female deity, Asherah, or the Queen of Heaven,” Römer told Haaretz. “There was certainly also the worship of the northern storm god Hadad (Baal).”

The plurality of deities was such that in an inscription by Sargon II, who completed the conquest of the kingdom of Israel in the late 8th century BCE, the Assyrian king mentioned that after capturing the capital Samaria, his troops brought back “the (statues of) gods in which (the Israelites) had put their trust.”

As the Yhwh cult evolved and spread, he was worshipped in temples across the land. Early 8th-century inscriptions found at Kuntillet Ajrud probably refer to different gods and cultic centers by invoking “Yhwh of Samaria and his Asherah” and “Yhwh of Teman and his Asherah.” Only later, under the reign of King Josiah at the end of the 7th century BCE, would the Yhwh cult centralize worship at the Temple in Jerusalem.

Nor, in ancient Israel, was Yhwh the invisible deity that Jews have refrained from depicting for the last two millennia or so.

In the kingdom of Israel, as Hosea 8 and 1 Kings 12:26-29 relate, he was often worshipped in the form of a calf, as the god Baal was. (1 Kings 12:26-29 explains that Jeroboam made two calves, for the sanctuaries at Bethel and Dan, so the people could worship Yhwh there and wouldn’t have to go all the way to Jerusalem. Ergo, in northern Israel at least, the calves were meant to represent Yhwh.)

In Jerusalem and Judah, Römer says, Yhwh more frequently took the form of a sun god or a seated deity. Such depictions may have even continued after the destruction of Jerusalem and the Babylonian Exile: a coin minted in Jerusalem during the Persian period shows a deity sitting on a wheeled throne and has been interpreted by some as a late anthropomorphic representation of Yhwh.

Römer even suspects that the Holy of Holies in the First Temple of Jerusalem, and other Judahite sanctuaries, hosted a statue of the god, based on Psalms and prophetic texts in the Bible that speak of being admitted in the presence of “the face of Yhwh.”

Not all scholars agree that the iconography of Yhwh was so pronounced in Judah. The evidence for anthropomorphic depiction “is not strong,” says Saul Olyan, professor of Judaic studies and religious studies at Brown University. “It may be that anthropomorphic images of Yhwh were avoided early on.”

The God of the Jews

In any case, many scholars agree that Yhwh became the main god of the Jews only after the destruction of the kingdom of Israel by the Assyrians, around 720 BCE.

How or why the Jews came to exalt Yhwh and reject the pagan gods they also adored is unclear.

We do know that after the fall of Samaria, the population of Jerusalem increased as much as fifteenfold, likely due to the influx of refugees from the north. That made it necessary for the kings of Judah to push a program that would unify the two populations and create a common narrative. And that in turn may be why the biblical writers frequently stigmatize the pagan cultic practices of the north, and stress that Jerusalem alone had withstood the Assyrian onslaught – thereby explaining Israel’s embarrassing fall to Assyria, while distinguishing the prominence and purity of Judahite religion.

Religious reforms by Judahite kings, mainly Hezekiah and Josiah, included abolishing random temple worship of Yhwh and centralizing his adoration at the Temple in Jerusalem, as well as banning the worship of Asherah, Yhwh’s female companion, and other pagan cults in the Temple and around the capital.

The Israelites don’t keep the faith

This transformation from polytheism to worshipping a single god was carved in stone, literally. For example, an inscription in a tomb in Khirbet Beit Lei, near the Judahite stronghold of Lachish, states that “Yhwh is the god of the whole country; the mountains of Judah belong to the god of Jerusalem.”

Josiah’s reforms were also enshrined in the book of Deuteronomy – whose original version is thought to have been compiled around this time – and especially in the words of Deut. 6, which would later form the Sh’ma Yisrael, one of the central prayers of Judaism: “Hear, O Israel, Yhwh is our God, Yhwh is one.”

But while Yhwh had, by the dawn of the 6th century BCE, become “our” national god, he was still believed to be just one of many celestial beings, each protecting his own people and territory.

This is reflected in the many biblical texts exhorting the Israelites not to follow other gods, a tacit acknowledgement of the existence of those deities, Romer explains.

For example, in Judges 11:24, Jephtah tries to resolve a territorial dispute by telling the Ammonites that the land of Israel had been given to the Israelites by Yhwh, while their lands had been given to them by their god Chemosh (“Will you not take what your god Chemosh gives you? Likewise, whatever Yhwh our god has given us, we will possess.”)

Snatching God from the jaws of defeat

The real conceptual revolution probably only occurred after the Babylonians’ conquest of Judah and arson of the First Temple in 587 B.C.E. The destruction and the subsequent exile to Babylon of the Judahite elites inevitably cast doubts on the faith they had put in Yhwh.

“The question was: how can we explain what happened?” Römer says. If the defeated Israelites had simply accepted that the Babylonian gods had proven they were stronger than the god of the Jews, history would have been very different.

But somehow, someone came up with a different, unprecedented explanation. “The idea was that the destruction happened because the kings did not obey the law of god,” Römer says. “It’s a paradoxical reading of the story: the vanquished in a way is saying that his god is the vanquisher. It’s quite a clever idea.

“The Israelites/Judahites took over the classical idea of the divine wrath that can provoke a national disaster but they combined it with the idea that Yhwh in his wrath made the Babylonians destroy Judah and Jerusalem,” he said.

The concept that Yhwh had pulled the Babylonians’ strings, causing them to punish the Israelites inevitably led to the belief that he was not just the god of one people, but a universal deity who exercises power over all of creation.

This idea is already present in the book of Isaiah, thought to be one of the earliest biblical texts, composed during or immediately after the Exile. This is also how the Jews became the “chosen people” – because the Biblical editors had to explain why Israel had a privileged relationship with Yhwh even though he was no longer a national deity, but the one true God.

Over the centuries, as the Bible was redacted, this narrative was refined and strengthened, creating the basis for a universal religion –  one that could continue to exist even without being tied to a specific territory or temple. And thus Judaism as we know it was established, and, ultimately, all other major monotheistic religions were as well.