WHEN THE ISRAELITES REACHED REPHIDIM (near the Sinai Peninsula in Midian), Moses was reunited with his father-in-law Jethro (Yitro), who had brought Moses' wife and two sons with him. Yitro had heard of God's deliverance of the children of Israel under the leadership of Moses and wanted to see for himself what God had done....
Recall that Midian (מִדְיָן) was a son of Abraham and Keturah (Gen. 25:1-6), and therefore the Midianites were cousins of the children of Jacob (i.e., the Israelites). Apparently the Midianites first settled east of the Jordan River (Gen. 25:6) though later they lived as nomadic shepherds in the Sinai Peninsula. It was a group of Midianite traders, you will remember, who "lifted Joseph from the pit" (Gen. 37:28) and sold him to the Ishmaelites (who in turn sold Joseph to Potiphar in Egypt).
Centuries later, Moses had fled to the "land of Midian" to escape Pharaoh's wrath (perhaps using the very same route he would later lead Israel during the Exodus). There he rescued the daughters of a man named Reuel (רְעוּאֵל, lit. a "friend [רֵעַ] of God"), who was also named Yitro (יִתְרו), the "priest of Midian" (Exod. 2:15-19; 3:1). Moses married Yitro's daughter Zipporah, had two sons, and spent forty years in Midian working for his father-in-law as a shepherd. It was in Midian that God appeared to Moses in the burning bush, and it was in Midian that God later revealed the Torah to Israel at Mount Sinai.
According to Jewish tradition, Moses' father-in-law was a pagan priest who "fattened calves for idolatry" (Sotah 43a). The midrash says he was a universalist who worshipped all the gods: "There was a not a god in the world that he [Jethro] did not worship" (Midrash Mechilta Yitro 1:1; cp. Exod. 18:11). It is unclear if Yitro knew of Moses' encounter with the burning bush at Sinai, but he wished him well as he left Midian to return to Egypt (Exod. 4:18-20). After the Exodus of Israel, however, Yitro later met up with Moses at Rephidim (Exod. 18:1-6). There he saw how the God of Israel had rescued the Jewish people and listened as Moses explained how the LORD had delivered them (Exod. 18:7-9). Then Jethro said, "Blessed be the LORD (בָּרוּךְ יְהוָה), who has delivered you out of the hand of the Egyptians and out of the hand of Pharaoh and has delivered the people from under the hand of the Egyptians. Now I know that the LORD is greater than all gods (עַתָּה יָדַעְתִּי כִּי־גָדוֹל יְהוָה מִכָּל־הָאֱלהִים)..." And Jethro brought a burnt offering and sacrifices to God; and Aaron came with all the elders of Israel to eat bread with Moses' father-in-law before God (Exod. 18:10-12). According to the sages, this event marked the moment of Yitro's teshuvah and conversion to the LORD God of Israel (יְהוָה אֱלהֵי יִשְׂרָאֵל).
After this, Yitro observed how Moses sat every day to judge the people "from morning to evening" (Exod. 18:13) and expressed concern that his son-in-law was taking on too much responsibility: "You and the people with you will certainly wear yourselves out, for the thing is too heavy for you. You are not able to do it alone." Yitro then prophetically advised Moses as follows:
You shall represent the people before God (אַתָּה לָעָם מוּל הָאֱלהִים) and bring their words to God, and you shall teach them about the statutes (הַחֻקִּים) and the laws (הַתּוֹרת), and make them know the way in which they must walk (הֲלָכָה) and what they must do. Moreover, look for able men from all the people, men who fear God, who are trustworthy and hate a bribe, and place such men over the people as chiefs (שָׂרִים) of thousands, of hundreds, of fifties, and of tens. And let them judge the people at all times. Every great matter they shall bring to you, but any small matter they shall decide themselves. So it will be easier for you, and they will bear the burden with you. If you do this, God will direct you, you will be able to endure, and all this people also will go to their place in peace" (Exod. 18:19-23)
Yitro wisely advised Moses to establish a hierarchy of judges (shoftim) to help bear the burden of governing the Israelites, thereby freeing Moses to be a more effective intercessor before the LORD. According to Midrash, Yitro's original name was Yeter (i.e., יֶתֶר, "remainder") but was changed to Yitro (i.e., יִתְרו, "His abundance") in honor of his wisdom and to indicate that he became a "convert" to the Jewish faith. Jewish tradition says that Yitro's descendants all became leaders in the Great Sanhedrin (i.e., the 71 member supreme court of ancient Israel). Later Yitro was called a "Kenite" (zealot) because his descendants were all zealous of the Torah (Judges 1:16).
After Yitro converted, he returned to his homeland where he attempted to convert the Midianites to the true faith (Exod. 18:27). He was unsuccessful, however, and later the Midianites became allied with the Moabites against the Jewish people (see parashat Balak). God finally directed Moses to destroy the Midianites (Num. 31:1), though he was unable to completely do so (Judges 6:1). (Note that Yitro's son Chovav later joined the Israelites and his descendants became incorporated into the tribe of Judah [Num. 10:30-32]).
After Moses restructured the politics of the camp according to the wisdom of Yitro, the great revelation of Sinai was given, including the awesome account of the giving of the Ten Commandments, the Ten "Words" or "Utterances" that were later inscribed on two tablets of stone (luchot) by the finger of God (Exod. 31:18; 32:15). For more information about the Ten Commandments, click the image below:
It is interesting to note that the earliest Jewish sages (i.e., pre-Mishnah interpreters) said that the Ten Commandments were not written five on one tablet and five on the other, but rather were written with all ten commandments written on both of the tablets. In other words, the Ten Commandments were given in duplicate form, and both tablets (i.e., copies of the contract) were deposited in the Holy Ark (and later at the Temple) to represent the terms of the agreement for both parties. This is similar to other ancient Near East treaties where one copy was given to the king and the other copy was given to the vassal.