Lift up your staff, and stretch out your hand over the sea and divide it, that the people of Israel may go through the sea on dry ground.
Trusting Moses and God, the people of Israel follow into an impossible situation. With Pharaoh now chasing them because his mind was changed and seeking to bring them back to slavery in Egypt, the people are very afraid.
Their impossible situation is being trapped between a large body of water and Pharaoh's army of chariots chasing them. There is no way for escape and Moses has brought them here.
God does not desert them, but gives them further reason to trust in him. By the power of God, Moses will part the waters so that Israel can pass through and escape the harm from Pharaoh.