Now this has got me wondering why God took all night to do it instead of doing it instantly like on tv. Was He testing their patience? Did He really need all night to do it? (I doubt it since He created the universe in 6 days) Or was there some other reason that no one knows about? Hmmmm...
Considering the number of people that were crossing the Red Sea it would have taken a long time. The census of men between 20-50 taken in numbers 1:46 was over 600,000...not including women and boys under 20 and men over 50. It is estimated that over 2 million Israelites crossed the Red Sea altogether, not to mention their flocks, herds, and cattle. Plus they were carrying their spoils of gold, silver, and clothing from the Egyptians. All things considered, it definitely would have taken all night for Israel and their possessions to cross the sea.