What this did was force both sides to go through with it: The Egyptians with attacking, and the Israelites with going across—just as God wanted to occur, so that His plan could move forward. There is also some symbolism in that the pillar was dark on the Egyptian side, which is an indication of wrath and judgment, darkness of death, and on the Israelite's side it was light. It says of Jesus, "In Him was light." Well, light stands for good, or favor. So He was comforting His people and giving the other side the willies. (You might want to write down Nahum 1:7-8—where it says that, in a nutshell, about His approach to the Assyrians.)
Now this stupendous miracle that occurred is unexplainable by natural means. If you go into a commentary and they start telling you, "Well, the wind did this, and. . ."—do not believe it, because there is no way a wind could pile up water on opposite sides of the people of Israel. That is what it says. It was a wall to their left and to their right. There is no wind in this world that could do it. Now, if it did, it would blow the Israelites and all their baggage to kingdom come. You have this 500,000 mile-per-hour wind, piling up water; and here are these Israelites yelling in terror and disaster. They would never make it.
But God piled that water up somehow on the one side, and He piled it up on the other; and then He sent a wind down the center, to dry the ground. And I think that the reason why Moses wrote it this way is because to them it looked like it was all one process. They could not explain it; but they felt the wind, drying the ground. So Moses stuck it in there, as whatever kind of an explanation he could come up with. He knew what it was though. The east wind made the sea into dry land.
At some point, God lifted the pillar of cloud; and the Egyptians pursued into the Red Sea. Now here (where most conservative scholars think the crossing was), the Red Sea was probably six to eight miles wide—at this point. So there was plenty of room to get quite a lot of Israelites (on the one end) and the Egyptian army (pursuing from the other end), and to get the entire Egyptian army between the walls of water before they came smacking down. This was a very large miracle that occurred. God had that water stand up in a heap, on both sides, for six to eight miles.
God causes the wheels of the chariots to fall off, and the Egyptians are stuck. So they begin to flee.
