When the children of Israel left Egypt, they were a mixed multitude. They were the survivors of over two hundred years of slavery.
Nechama Leibowitz wrote that they displayed timidity, scepticism, ambivalent and twisted thinking, pettiness and grumbling, the outcome of long, hard bondage. She also pointed out that on the other hand, they also showed intense faith and trust in G-d, and quoted R’ Eliezer who said that they deserved great credit for following Moshe into the desert, on the promise of redemption, leaving behind a land of culture and of plenty. They were led by the long route towards Canaan and this was commented on by Rambam.
Rambam regarded the diversion into the wilderness not only as a preventive act to stop them running back to Egypt, but also as an opportunity for them to become accustomed to hardship in order to toughen them for the fight to conquer the Promised Land. R’ Eli Munk added that they would have an increased appreciation of the land when they finally arrived.
When the Egyptians pursued them, they were overawed at the sight and they were afraid. Nechama Leibowitz quoted Ibn Ezra who wrote that they were psychologically incapable of fighting against those who had been their lords and masters for over two hundred years. They had a slave mentality and no experience of warfare. Their grumbling at this point mirrored their natural subservience and they are quoted saying to Moshe “were there no graves in Egypt that you had to take us to die in the wilderness?” and “would it not have been better to serve Egypt than to have to die in the wilderness?” They looked at the future with trepidation, and their yearnings were for the past rather than for the unknown that lay ahead.
As they stood with their backs to the Reed Sea, they were frozen in fear, and Moshe said to them “Do not fear, stand fast and see the salvation of G-d that He will perform for you today: for as you have seen Egypt today, you shall not see them ever again. G-d will do battle for you, and you shall remain silent”.
A major miracle was required, described here in detail and it consisted of the parting of the Sea, the Israelites walking through on dry land, and the Egyptians drowning as they were caught by the water coming back as they pursued the people. In summary, “on that day, G-d saved Israel from the hand of Egypt, and Israel saw the Egyptians dead on the seashore. Israel saw the great hand that G-d inflicted upon Egypt, and the people revered G-d and they had faith in G-d and His servant Moshe.” They were led in their praise of G-d to sing a great song, which is recited every day in prayers to this day.
It was shortly after this that they came to a spring with bitter waters and the people of Israel began complaining again. Yeshayahu Leibowitz wrote that this sequence of events demonstrated that faith cannot be sustained by miracles. Faith has to be nurtured in the everyday mundane nature of human existence.