Why did God send Moses into the desert for 40 years to herd sheep before sending him back to Egypt?
God sent Moses to the backside of the desert for forty years because he had relied on Egypt's pomp and circumstance and thought he could deliver Israel by his own power. God could not use him in that condition. After Moses became a lowly shepherd, God could send him back to Egypt.
Les teaches that Moses had been the second man of Egypt, with all the power, pomp, and circumstance of Pharaoh behind him, and he thought he could lead the children of Israel out, but God could not use him. So God sent him to the backside of the desert to herd sheep for forty years. Then, as a lowly shepherd—probably kind of smelly—Moses was in a place where God could say, “Moses, I want to send you back to Egypt.” Les explains that this is the way God works: He cannot use the pomp and circumstance of this world.