The Talmud (Zevachim 116a) quotes an argument between R. Yehoshua who argued that Yitro visited Moshe before the Decalogue was declared, which follows the order of the Torah, and R. Eleazar ha-Modia, who argued that Yitro’s visit was after the Decalogue. This argument continued amongst the commentators.
Ibn Ezra (long commentary on 18:1) follows R. Eleazar ha-Modia’s opinion and presents five reasons why he thinks chapter 18 is not recorded in chronological order. One, 18:5 refers to Yitro coming to Moshe who was camped in the desert by the mountain of G-d, Mount Sinai, and Ibn Ezra (on 18:5) believes that the word camped means for an extended time, which could only have been after the Decalogue. Two, Yitro offered sacrifices but there is no mention of an altar until after the giving of the Torah. Three, 18:16,20 refer to laws, which would seem to only be possible after the giving of the Torah. Four, Bemidbar 10:29-32, appears to record that Yitro was with the Jewish people in the second year, but 18:27 records that he left. Five, Devarim 1:9-19, which also records the establishment of the judicial system, implies that the people were ready to travel into the land of Israel after the system was established, while in chapter 18 the people were not going to travel for some time. Ibn Ezra (see also Tosafot, Avodah Zara, 24b, Yitro and Cassuto, 1967, pp. 211,212) explains that the section was recorded at this point in the Torah to contrast Amalek and Yitro, that Amalek harmed the Jewish people while Yitro was good to the Jewish people.
Ramban (on 18:1) disagrees with the Ibn Ezra. He claims that Yitro visited Moshe before the giving of the Torah, left and then returned in the second year. Ramban points out that 18:1 records that Yitro heard the wonders of the Exodus but does not state that he heard about the declaration of the Decalogue. Also 18:8 records that Moshe told Yitro the complete story of the Exodus but again there is no mention of the Decalogue, and 18:9,10, which record Yitro’s response, again only refer to the Exodus and not the Decalogue. Ramban argues that if Yitro had really visited after the Decalogue, then 18:1-10 should have referred to the Decalogue.
Abravanel (1997, pp. 260-263) follows the Ramban that Yitro visited Moshe before the giving of the Torah. He suggests that the altar used by Yitro was the one that Moshe built after the battle with Amalek, 17:16, and that the laws referred to in chapter 18 are the laws of Shabbat and civil laws that were taught at Mara, 15:25. Note, Luzzatto (on 18:15), who also follows this approach that Yitro visited Moshe before the Decalogue, suggests that the laws referred to in 15:25 were monetary laws, and other issues concerning personal disagreements and public order, see also Ramban on 15:25.
Abravanel (see also Tosafot, Avodah Zara, 24b, Yitro) suggests that while Yitro advised Moshe about the judicial system before the giving of the Torah, Moshe only implemented the system afterwards. Thus, Devarim 1:19 can record to the implementation of the judicial system when the people were ready to travel, and Shemot 18:24-26 is recorded out of chronological order. Abravanel believes that Yitro stayed with the people until the second year of the people’s stay in the desert in accordance with Bemidbar 10:29-32, and then Shemot 18:27, which records that Yitro left before the Decalogue, is also recorded out of chronological order.
Benno Jacob (1992, pp. 494,495) follows the Abravanel’s approach and points out that the more logical assumption is that Moshe’s family went to visit him immediately after the Exodus instead of waiting another year to see him. Jacob (p. 498) claims the altar could have been an “ad hoc altar,” since it is not difficult to build an altar, and hence there was no need to mention the building of an additional altar when Yitro offered his sacrifices. Furthermore, he (p. 502) argues that the establishment of the judicial system must have occurred at a later date, since the selection of so many judges was “a difficult and time–consuming task which had to be undertaken with great care. It surely could not have been accomplished during the few days which remained till their arrival at Sinai.”
My inclination is to follow the approach that Yitro visited Moshe before the Decalogue as argued by the Ramban, Abravanel, Luzzatto and Benno Jacob. With regard to Ibn Ezra's questions, I am not convinced that the word camping in 18:5 implies that Moshe had been camping for a long time by Mount Sinai, though it would imply that Yitro arrived at Mount Sinai after Moshe. With regard to the altar, Benno Jacob makes sense that it is not difficult to build an "ad hoc altar." The reference to laws in 18:16 could be that Moshe heard various cases, and then G-d told him the law relevant to the particular case. This could mean that G-d spoke to Moshe on the spot, or it could be that G-d spoke to Moshe every few hours or at the end of the day. 18:20 would then mean that Yitro advised Moshe to pass on to the people the laws that G-d had told him about the cases. With regard to the relationship between this section and Bemidbar 10:29-32, I do not think that Yitro is being referred to in Bemidbar 10:29-32, so Yitro could have left the people before the Decalogue as indicated by 18:27, see our discussion on Bemidbar 10:29-32, "Confusion in the family." Finally, I think Abravanel and Benno Jacob make sense that even if Yitro visited Moshe before the Decalogue, Moshe only implemented Yitro's advice afterwards, and then Devarim 1:9-19 can accord with Shemot 18:24-26. It is also possible that in Devarim 1, where Moshe was reminding the people of past events, Moshe was not giving the exact timing of each event in relation to the other events.
Yet, there is a stronger question that Ibn Ezra did not refer to in his long commentary, but he did mention in his short commentary on 18:1. Did Moshe have the time to sit and judge the people at Mount Sinai before the Decalogue?
Rashi (on 19:3,8,9) explains that once the people reached Mount Sinai, Moshe went up to Mount Sinai once a day to speak to G-d, and then he could not have been judging the people, from morning to night, 18:13. However, maybe there was a break in the days that Moshe went up to Mount Sinai to speak to G-d. 19:11 specifically refers to the people being ready on the third day, which means that on the following day, Moshe was "free." Rashi (on 19:11) explains that Moshe built the altar for the ceremony that is recorded in Shemot 24 on that day, but this is because he thinks that this ceremony occurred before the Decalogue (see Rashi on 24:1). However, if one believes that the ceremony occurred after the Decalogue, then Moshe could have judged the people on that day.
With this understanding, Yitro came to Mount Sinai on the day when G-d told Moshe the instructions recorded in 19:10-13, and Moshe judged the people the following day during his one "free" day. Yet, was this judging necessary at this time? It could not wait until after the Decalogue? Was there a need or desire to resolve all the conflicts amongst the people prior to the Decalogue?
My thought is that the discussion of Moshe judging the people and Yitro's advice to establish a judicial system is to teach the lesson prior to the Decalogue that societies need judicial systems. The Decalogue was part of the covenant which was a system of laws, and some people, such as anarchists, might question why is there a need for laws? The case of Moshe judging the people prior to the Decalogue and Yitro's advice demonstrates the need for laws since people naturally have disputes and there needs to be laws and a system to deal with these conflicts. Accordingly, Moshe had to make time to judge the people before the Decalogue to show that laws and especially civil laws are necessary for a society. Furthermore, this advice to establish a judicial system came from Yitro, a "foreigner," which shows that judicial systems are a universal need. (Note, if one wants to follow the idea that Yitro visited after the Decalogue, then this reason could explain why his visit was recorded before the Decalogue.)
To conclude, my inclination is that Yitro visited Moshe before the Decalogue, but Moshe implemented his advice after the Decalogue. As to when Yitro left, I doubt he left before the Decalogue since that was such an amazing event, but he could have left any time afterwards without any connection to the events in Bemidbar 10:29-32.
This understanding means that 18:1-4 occurred sometime after the Exodus from Egypt, but it took some time for Yitro and Moshe’s family to reach Moshe. 18:5-12 occurred after the people were already at Mount Sinai on the day when G-d told Moshe the instructions of 19:10-13. 18:13-23 occurred on the following day prior to the Decalogue, and 18:24-27 occurred sometime after the Decalogue, possibly right before the people left Mount Sinai.
Benno Jacob (1992, pp. 494,495) follows the Abravanel’s approach and points out that the more logical assumption is that Moshe’s family went to visit him immediately after the Exodus instead of waiting another year to see him. Jacob (p. 498) claims the altar could have been an “ad hoc altar,” since it is not difficult to build an altar, and hence there was no need to mention the building of an additional altar when Yitro offered his sacrifices. Furthermore, he (p. 502) argues that the establishment of the judicial system must have occurred at a later date, since the selection of so many judges was “a difficult and time–consuming task which had to be undertaken with great care. It surely could not have been accomplished during the few days which remained till their arrival at Sinai.”
My inclination is to follow the approach that Yitro visited Moshe before the Decalogue as argued by the Ramban, Abravanel, Luzzatto and Benno Jacob. With regard to Ibn Ezra's questions, I am not convinced that the word camping in 18:5 implies that Moshe had been camping for a long time by Mount Sinai, though it would imply that Yitro arrived at Mount Sinai after Moshe. With regard to the altar, Benno Jacob makes sense that it is not difficult to build an "ad hoc altar." The reference to laws in 18:16 could be that Moshe heard various cases, and then G-d told him the law relevant to the particular case. This could mean that G-d spoke to Moshe on the spot, or it could be that G-d spoke to Moshe every few hours or at the end of the day. 18:20 would then mean that Yitro advised Moshe to pass on to the people the laws that G-d had told him about the cases. With regard to the relationship between this section and Bemidbar 10:29-32, I do not think that Yitro is being referred to in Bemidbar 10:29-32, so Yitro could have left the people before the Decalogue as indicated by 18:27, see our discussion on Bemidbar 10:29-32, "Confusion in the family." Finally, I think Abravanel and Benno Jacob make sense that even if Yitro visited Moshe before the Decalogue, Moshe only implemented Yitro's advice afterwards, and then Devarim 1:9-19 can accord with Shemot 18:24-26. It is also possible that in Devarim 1, where Moshe was reminding the people of past events, Moshe was not giving the exact timing of each event in relation to the other events.
Yet, there is a stronger question that Ibn Ezra did not refer to in his long commentary, but he did mention in his short commentary on 18:1. Did Moshe have the time to sit and judge the people at Mount Sinai before the Decalogue?
Rashi (on 19:3,8,9) explains that once the people reached Mount Sinai, Moshe went up to Mount Sinai once a day to speak to G-d, and then he could not have been judging the people, from morning to night, 18:13. However, maybe there was a break in the days that Moshe went up to Mount Sinai to speak to G-d. 19:11 specifically refers to the people being ready on the third day, which means that on the following day, Moshe was "free." Rashi (on 19:11) explains that Moshe built the altar for the ceremony that is recorded in Shemot 24 on that day, but this is because he thinks that this ceremony occurred before the Decalogue (see Rashi on 24:1). However, if one believes that the ceremony occurred after the Decalogue, then Moshe could have judged the people on that day.
With this understanding, Yitro came to Mount Sinai on the day when G-d told Moshe the instructions recorded in 19:10-13, and Moshe judged the people the following day during his one "free" day. Yet, was this judging necessary at this time? It could not wait until after the Decalogue? Was there a need or desire to resolve all the conflicts amongst the people prior to the Decalogue?
My thought is that the discussion of Moshe judging the people and Yitro's advice to establish a judicial system is to teach the lesson prior to the Decalogue that societies need judicial systems. The Decalogue was part of the covenant which was a system of laws, and some people, such as anarchists, might question why is there a need for laws? The case of Moshe judging the people prior to the Decalogue and Yitro's advice demonstrates the need for laws since people naturally have disputes and there needs to be laws and a system to deal with these conflicts. Accordingly, Moshe had to make time to judge the people before the Decalogue to show that laws and especially civil laws are necessary for a society. Furthermore, this advice to establish a judicial system came from Yitro, a "foreigner," which shows that judicial systems are a universal need. (Note, if one wants to follow the idea that Yitro visited after the Decalogue, then this reason could explain why his visit was recorded before the Decalogue.)
To conclude, my inclination is that Yitro visited Moshe before the Decalogue, but Moshe implemented his advice after the Decalogue. As to when Yitro left, I doubt he left before the Decalogue since that was such an amazing event, but he could have left any time afterwards without any connection to the events in Bemidbar 10:29-32.
This understanding means that 18:1-4 occurred sometime after the Exodus from Egypt, but it took some time for Yitro and Moshe’s family to reach Moshe. 18:5-12 occurred after the people were already at Mount Sinai on the day when G-d told Moshe the instructions of 19:10-13. 18:13-23 occurred on the following day prior to the Decalogue, and 18:24-27 occurred sometime after the Decalogue, possibly right before the people left Mount Sinai.
The narrative order of chapter 18 is to record all the events relating to Yitro together even though this meant not following the chronological order of the events, see Tosafot, Avodah Zara, 24b, Yitro. Abravanel compares this to Shemot 16:33-35, which records that Moshe, told Aharon to take the mahn and put in it the aron, an event that also is recorded out of chronological order. Another example is Bereshit 11:32, which records the death of Terah out of chronological order in order to complete the discussion concerning Terah. In both cases, several references to the same person (Terah) or item (mahn) are recorded together even if some of the events regarding the person or item occurred at a later time. (Note, following this logic, one might be tempted to argue that also the events of 18:13-23 are recorded out of chronological order, but 18:13 is connected to 18:12 through the words, "on the morrow.")
Bibliography:
Cassuto, Umberto (1883-1951), 1967, A commentary on the book of Exodus, Jerusalem: The Magnes Press
Jacob, Benno (1869-1945), 1992, The second book of the Bible: Exodus, translated with an introduction by Walter Jacob, Hoboken: Ktav Publishing House.