Q: #337. Why, and when, did Moses send his wife and sons back to Jethro?
By: Steve Shirley
A: Interesting question! I must admit that until now, I have actually "read over" this in my Bible reading. Answering this requires putting two sections of Exodus together: (Ex 4:18-26) and (Ex 18:1-7).
It is not possible to know FOR SURE from scripture when Moses sent His wife Zipporah, and two sons Gershom (the oldest: Ex 2:22) and Eliezer, back to his father-in-law Jethro. However, nearly all scholars believe it was right after the events in (Ex 4:18-26).
We know that originally, they left for Egypt with Moses (Ex 4:18-20). In the midst of their journey, as they were at an "encampment" (KJV says "inn"), God struck Moses with a very serious illness for failing to circumcise his son (likely the younger one Eliezer). It appears that he was so sick that he was unable to do it himself, so Zipporah did it. Her words that followed to Moses were "Surely you are a husband of blood to me!" (Ex 4:25). Most believe that she was opposed to infant circumcision (as were her Midianite people), so Moses did not perform the circumcision in order to please her. However, when she saw that God would take her husband's life for failing to do so, she did it herself, but the ritual disgusted her, thus her words to Moses.
After this event, we see Moses meeting up with Aaron and heading for Egypt (Ex 4:27-31). We do not hear about Zipporah and the two boys again until (Ex 18:1-7).
In (Ex 18:1-7) we see that Jethro is going to go visit Moses, taking with him Zipporah "after he had sent her back" (Ex 18:2). So, clearly, Moses had sent her away to Jethro at some point. Verses 1-7 tell us about this visit of Jethro, and the reunion of Zipporah and the two sons with Moses.
Because there is no mention of Zipporah and the boys after the circumcision until the reunion, nearly everyone agrees that they likely returned to Jethro right after that event. Therefore, the time for their return was right before Moses went to Egypt. I believe they were probably reunited with Moses within a year. I base this on three things: 1. The time period between when Moses separated from Zipporah and confronted Pharaoh seems to be fairly short. 2. The 10 plagues started, which I believe lasted about 4-5 months (I discuss this here). 3. They reunited at Mt. Sinai (Ex 18:5), and this was three months after the Israelites had left Egypt (Ex 19:1).
The reason why Moses sent his wife and children back to Jethro is not mentioned
in Scripture. There are several guesses though.
To protect them from the dangers that he knew awaited him in Egypt. (This is the most common thought)
He did not want them to distract him from the mission he had ahead.
He did not want to delay his mission while waiting for his son to recover from his circumcision.
He was angry at his wife for her words. (This seems unlikely)
Aaron urged him to. (Also unlikely)
Studying this was interesting to me because I had assumed that Moses had his wife and boys with him in Egypt. You see them with him in The Ten Commandments movie during the Passover . Apparently, this is not true (as are many other things in that movie), but I still like the movie .