Then Moses let his father-in-law depart is literally “And Moses let go his father-in-law.” The same verb was used in the demand to the Pharaoh to “let my people go” (5.1), but the context here is quite different. There is no suggestion in the Hebrew that “Jethro” was not free to go until Moses gave him permission. New Jewish Publication Society’s Tanakh and others have “Then Moses bade his father-in-law farewell,” which may mean more than simply “said good-bye to Jethro,” as Good News Translation expresses it. New International Version has “Then Moses sent his father-in-law on his way.” (See a similar context in 4.18.)

Quoted with permission from Osborn, Noel D. and Hatton, Howard A. A Handbook on Exodus. (UBS Helps for Translators). New York: UBS, 1999. For this and other handbooks for translators see here .