First, the response of Jethro to Moses' news of the Exodus from Egypt helps us see why God orchestrated those events in such a way:
Jethro rejoiced for all the good that the Lord had done to Israel, in delivering them from the Egyptians. Jethro said, "Blessed be the Lord, who has delivered you from the Egyptians and from Pharaoh. Now I know that the Lord is greater than all gods, because he delivered his people from the Egyptians when they dealt arrogantly with them" (vs. 9-11)
So impressed is Jethro with Moses' God, he provides a burnt offering and sacrifices to the Lord. Jethro's response is typical of what people will conclude when they hear of the Exodus: God is with the Israelites, and He is stronger than all the might of the Egyptians and their gods! These are important conclusions that we can draw from the Exodus yet today.
Second, Jethro provides some practical advice to Moses in his governance of the people. Moses is the leader of this group, and there is a lot of administration to do. Moses has been "micro-managing" everything, deciding even minor disputes among the people. Jethro proposes a new organizational chart for the nation, with able captains and lieutenants appointed over groups of ten, fifties, hundreds, and thousands (vs. 21). In this way, Moses' time and energy can be better stewarded. His efforts should be spent, Jethro counseled, in teaching the people the statutes and instructions (the law), making known to them the way they are to go and the things they are to do (vs. 20).
Does this mean that Jethro was the first to propose the writing down and encoding of the Law of Israel for education and reflection? Do we have Jethro to thank for the fact that we have this book to study!?