Yonatan Kohn - Notes on Yitero
"Jethro, priest of Midian, father-in-law of Moses, heard all Gd did for Moses and for his nation Israel, for Gd took Israel out of Egypt" (18:1). Having heard of the miracles performed for the fledgling nation, Jethro comes, escorted by Moses's wife and two sons, to greet Moses in the shadow of Mt. Sinai to investigate and celebrate these supernatural wonders. What did Jethro hear that so moved him? The midrash Yalqut cites three opinions. R Joshua says, "He heard of the war of Amaleq and came." R Elazar the Moda'ite says, "He heard of the giving of the Torah* and came." R Eliezer says, "He heard of the splitting of the sea and came." It is quite possible that Jethro heard of all these miracles. If so, what is the source for dispute in this midrash? Keli Yaqar suggests that all opinions agree that Jethro heard of all the miracles, as the verses indicate. They debate only what causes Jethro "to come" (each opinion uses this term in his explanation) with Moses's wife and sons. What motivated Jethro to actively reunite Moses with his family?
According to R Joshua, Jethro heard of the war of Amaleq. Jethro's family was connected to Amaleq (as is evident from a later Amaleq battle account, Samuel I 15:6), and as the conflict of Israel vs. Amaleq was to be an eternal war (17:16), Jethro sought to protect his family from becoming an enemy of Israel by association. Thus, his efforts to reunite Moses with his family were firmly rooted in the desire to establish familial ties and loyalties between Moses and Israel and his own people.
R Elazar the Moda'ite explains that Jethro heard of the giving of the Torah. Jethro understood that just Israel was commanded to separate from spouses before they accepted the Torah (19:15), the constant prophet Moses had seen fit to separate for a long period. Therefore, Jethro brought Moses's wife back to him to live with him- as befits man to live in a family-centered home.
R Eliezer suggests Jethro came after hearing of the splitting of the sea. Moses had formally divorced his wife, and according to the Talmud (Sanhedrin 22a) unifying a separated (according to Keli Yaqar) couple is "as difficult" as the splitting of the sea. The Talmud's analogy likens the reuniting of a separated couple to the splitting of the sea. Because a couple's bond is a natural one, like the bonding of bodies of water, their supernatural separation is fierce and resolute. Yet when Jethro saw that it was Gd's will that they should be reunited, their match should be successful, like the calm of combined waters. Jethro originally feared that after a legal divorce, it would be impossible to reconnect and live together again in harmony. However, after he heard of the splitting of the sea and the natural and complete restoration of the waters' original flow, he understood that even a separated couple could be reunited happily. Jethro's push to reunite Moses with his daughter Zipora was thus rooted in the hope and belief instilled by the miracle of the splitting- and subsequent calming- of the sea.
*Both Rashi (to 18:13) and Nahmonides (to 18:1) cite the Rabbinic Tradition that Jethro's visit may have been after the divine Revalation at Sinai, outlined later in the reading, based on a series of other verses. They also present other possibilities. Why the Torah may have changed the order of these events may be based on thematic considerations relating to conversion and the Sinai experience.

