וַיְשַׁלַּ֥ח מֹשֶׁ֖ה אֶת־חֹתְנ֑וֹ וַיֵּ֥לֶךְ ל֖וֹ אֶל־אַרְצֽוֹ׃ (פ)
Kemudian Musa melepas mertuanya pergi, lalu ia pulang ke negerinya sendiri.
Sefer HaMiddot
10. At the time when a student comes to hear Torah from a rabbi, the student's evil -- that is, the impure husks (klipos) created by the evil in him, also come to hear and draw from it. However, when each student hears only what is relevant to his soul, as was described above, the evil spirits (klipos) flee, and are not able to hear. Yet there is a subtle evil (klipa) which is close to holiness, that will only flee when there is within the Torah teaching a message of salvation of Israel, then it also flees. A hint for this from Scripture: "And Moshe sent his father-in-law" -- if one learns this passage according to the opinion that Yitro (the father-in-law of Moses) came and went his way before the giving of the Torah.