God has just brought the people through the red sea, saving them from Pharaoh and his chariots. They have been saved, they believed, and they worshiped. What comes next? The answer, like that for the Christian, is sanctification; the long hard process of being conformed to the holiness of God. They had left Egypt, making a decisive break with sin, but the process of change still had to be undertaken. The wilderness was a hard place, but it is also the place they meet with God, and learned to trust God completely before they entered the Promised Land. There is a similar journey for each of us, as believers, too.