Religious texts are not meant to be taken literally and largely deal with symbols, myths and metaphors. The people who wrote this texts came from a 'pre-modern' society. We tend to assume that people in the past were like us but in fact their spiritual lives were rather different.
In particular, they evolved around two ways of thinking, which scholars have called 'mythos' and 'logos'. Myth was not concerned with practical matters, but with meaning. The 'mythos' of a society provided people with a context that made sense of their day to day lives. It was also rooted in what we would call the 'unconscious' mind.
The various mythological stories, which were not meant to be taken literally, were an ancient form of psychology. When people told stories about heroes who descended into the underworld, struggled through labyrinths, fought with monsters, they were bringing to light the regions of the subconscious realm, which is not accessible to purely rational investigation. Without a cult or mystical practice, the myths of religion would make no sense.
In the pre-modern world, people also had a different view of history from us. They were less concerned with what actually happened, but more concerned with the meaning of an event. Thus, we don't know what really occurred when the Israelites escaped from Egypt. The story has been written as a myth, and linked with other stories about rites of passage, immersion in the deep, and gods splitting a sea into two to create a new reality.
To ask whether the Exodus in Egypt took place exactly as recounted in the Bible or to demand scientific evidence to prove that it is factually true is to mistake the nature and purpose of this story. It is to confuse 'mythos' with 'logos'.
'Logos' was the rational, pragmatic and scientific thought that enabled men and women to function in this world. Unlike 'mythos', 'logos' must relate exactly to facts and correspond to external reality. 'Logos' is practical and logical. Myth was not reasonable.
You cannot make 'mythos' the basis of a pragmatic policy. If you did, the results would be disastrous. When, for example, Pope Urban II summoned the First Crusade (1095), his plan belonged to the realm of 'logos'.
He wanted the knights of Europe to stop fighting one another, and to expend their energies in a war in the Middle East and so extend the power of the Church. But when this expedition became entangled in biblical lore, and apocalyptic fantasies, the results were catastrophic, militarily and morally.
But 'logos' has its limitations too. Scientific arguments can make no sense of tragedy. 'Logos' cannot answer questions about the ultimate value of human life. A scientist could discover new facts about the physical universe, but he cannot explain the meaning of life. That is the preserve of 'mythos'.
However, all religions contain truths and errors. By asking a government to enforce religion on its subjects, this denies the latter their basic religious freedom. It is the surest way to corrupt both religion and to arrest the spiritual growth of the people. No religion has a monopoly on spirituality.
This is because spirituality is not about how often you pray, fast and visit your mosque, church, synagogue or temple. It is about serving your fellow man and living by the virtues of humility, benevolence, tolerance and universal love. And all faiths, be they either Christian, Jewish, or Muslim fail this crucial test if they becomes theologies of rage and hatred.