The actor Christian Bale has said that Moses was "likely schizophrenic and one of the most barbaric characters I ever read about in my life", which may illuminate the way he plays the character in Ridley Scott's upcoming film Exodus: Gods and Kings.
But what light does it cast on the historical figure of Moses? The rather surprising answer is: none. There is no historical figure of Moses, and no reason from archaeology or history to suppose any of the exodus story is true.
Since the central rite of Jewish identity is the Passover festival, which commemorates the moment that Moses freed his people from slavery in Egypt, the absence of evidence outside the Bible story is potentially embarrassing, says Rabbi Laura Janner-Klausner, who leads Reform Judaism in Britain. "You have to distinguish between truth and historicity," she said.
The controversy so far has usually dealt with the miraculous elements of the story - the plagues of blood and frogs and locusts, God's slaughter of the firstborn children of Egypt and, especially, the parting of the Red Sea. One of the earliest attempts to demythologise the story occurred with the suggestion that the Red Sea was actually "the sea of reeds", a swamp that might have been temporarily cleared by wind. Scott's film turns God's parting of the sea into an earthquake.
But the problem with historical evidence goes much deeper. "Moses himself has about as much historic reality as King Arthur," archaeologist Philip Davies famously concluded. A more moderate conclusion comes from the historian Tom Holland: "The likelihood that the biblical story records an actual event is fairly small."
Cyprian Broodbank, professor of archaeology at Cambridge University, wrote that the exodus was "at best a refracted folk memory of earlier expulsions of Levantine people" following the reconquest of the Nile delta by the Egyptian king Ahmose around 1530BC.
This date is about 900 years earlier than the period in which the Hebrew Bible is supposed to have been codified and written down, including its first five books that were supposedly written by Moses himself. There is no archaeological evidence for the biblical story, and certainly no extra-biblical evidence, in Egyptian inscriptions. Not even the Bible account claims that the Israelites were employed as slaves to build the pyramids as they are in Hollywood. They are simply slaves.
Yet there are tantalising glimpses in the story of something that may be more than mere folk tale. For a start there is the name "Moses" itself, which is Egyptian rather than Hebrew, suggesting the stories drew on memories of real interactions. Holland points out that Moses is mentioned 137 times in the Koran. There were times in the 16th and 17th centuries BC when tribal groups from the eastern Mediterranean were found in what is now northern Egypt. And the story of Moses has a strange echo in the life of Egyptian pharaoh Akhenaten, the first monotheist known to history. He reigned from 1352 to 1338BC, and proclaimed that there was only one true God, Aten, the sun disc. All others were false, their images destroyed and their names erased. When Akhenaten died, the old religious system revived and then obliterated his memory and, had it not been for the chance discovery of his tomb in the 19th century, the experiment would have been forgotten. As historian Jan Assmann puts it: "Moses is a figure of memory, not of history, whereas Akhenaten is a figure of history, but not of memory."
In the Bible, Moses did not invent monotheism. He had it revealed to him by the One God, who appeared in a burning bush and would not give his name - "I am that I am". Unlike Akhenaten, who appeared alongside his God in sculptures, Moses was very clear about the difference between himself and God. He is horrified when God tells him to return to Egypt and lead the Israelites out, and arranges for his brother Aaron to be the front man and deliver the speeches.
"When you're frightened, you internalise a voice that says 'why me, why do I have to do it?' - that's the Moses voice," says Janner-Klausner. "What matters to me is that the language and the modelling of that kind of leadership is extremely true - to have a flawed leader, a reluctant leader. The question I ask of the story is: is there enduring truth that will move me, move the people I'm involved with, and give them liberation? Yes."
Alex Goldberg, an Orthodox rabbi, takes an unemphatic view of the historicity of Moses. "I believe that Moses existed, but that's not the point. From a Jewish perspective, what matters is the theophany on Sinai and receiving the laws. We have faith that the Torah was given to us, and that there was a God event in Sinai."
Having little historical evidence for biblical narratives is not the same as having none. Egyptian and Assyrian documents of a much later date than the supposed exodus clearly mention the Hebrews, and archaeology shows that the inhabitants of inland Palestine, which is now the occupied West Bank, were refraining from pork by about 1000BC, while the people nearer the sea, in what is now Israel, were happily eating pigs.
Some features of what would become Judaism were clearly established a very long time ago. But there is no archaeological evidence for the genocide of the Canaanites and even if David and Saul and Solomon all existed, they must have been tribal leaders and not the kings of the Bible. Yet what gives all these figures life is not their grandeur but their frailty. This humanity serves to magnify the power and otherness of God.
And the story of the exodus has a power entirely independent of its historical truth. By believing that it happened, and that it was in a sense, still happening in eternity, people brought and still bring liberation into their lives today. The American civil rights movement could be seen as an attempt to re-imagine black Americans as Israelite slaves, led out of bondage to the promised land. For many, regardless of whether he existed, Moses is as alive today as he ever was.
'White' comment offends
Media baron Rupert Murdoch sparked fury on Twitter after claiming Egyptians are white.
Exodus: Gods and Kings has been criticised for a lack of ethnic diversity among its leading actors. Murdoch, owner of News Corp, tweeted: "Moses film attacked on Twitter for all-white cast. Since when are Egyptians not white? All I know are."
That was followed by: "Everybody-attacks last tweet. Of course are Middle Eastern, but far from black." He then added: "OK, there are many shades of colour. Nothing racist about that, so calm down!"
- additional reporting Independent