Sefer Vayikra ends with God communicating with Moshe on Mt. Sinai, while Sefer Bamidbar begins with God communicating with Moshe in the Sinai Desert, in the אהל מועד (Tent of Meeting). This transition occurs because after the Mishkan was built, God communicated with Moshe there rather than on Mt. Sinai (see Rashbam, Ibn Ezra and Chizkuni). However, Mt. Sinai is also in the Sinai Desert; moving the place of their communication to the Mishkan – which was near Mt. Sinai – was not a major location change. [It was still significant because the Mishkan traveled with the nation, and God would continue to communicate with Moshe within it.] It was,therefore, unnecessary to mention the Sinai Desert (just the אהל מועד), leading the Midrash (Bamidbar Rabba 1:7) to say that the desert is mentioned to teach us that one must be like a desert, ownerless, in order to acquire wisdom and Torah.
Although the Sinai Desert is located on the Sinai Peninsula, the two are not synonymous, as the Sinai Peninsula contains several deserts. Currently, the Sinai Peninsula includes the area between the two forks of the Red Sea (the bottom of the triangle), up to the Mediterranean Sea (its northern border) and east to the Negev (its eastern border, which is also Israel’s southwestern border). Originally, much of the Negev was also considered part of the Sinai Peninsula. The Talmud (Shabbos 89a) seems to say that the various deserts on the peninsula are all one and the same, with the Sinai Desert being just one of its names. However, as Tosfos points out, this can’t be true, as one of the names (מדבר קדמות) refers to an area east of the Jordan River, which is clearly not on the peninsula. Maharsha explains the Talmud to be referring to the different deserts in which the Mishkan was erected over the 40 years of wandering, not that the same desert had five different names. Midrash HaGadol (Bamidbar 1:1) says explicitly that the Sinai Desert is not the same desert as other deserts mentioned by the Talmud.
Even though the Sinai Desert is distinct from the Paran Desert, which was the nation’s next stop (Bamidbar 10:12), deserts bearing different names seem (at least at first glance) to have been part of the Paran Desert. For example, the scouts left from the Paran Desert (13:3), and when they returned, it was to Kadesh, which was in the Paran Desert (13:26). Yet, there is also a Kadesh Desert (Tehillim 29:8), indicating that the Kadesh Desert was part of the Paran Desert. It is possible, though, that what had been known as מדבר פארן later became known as מדבר קדש, rather than the Kadesh Desert being a subset of the Paran Desert. Although Dovid fled to the Paran Desert after Shmuel died (Shmuel I 25:1), he might have started referring to it differently afterwards. It’s also possible that he wasn’t using a proper noun, but referring to the desert that included Kadesh, i.e. the Paran Desert. It should be noted that when Midrash HaGadol lists the 10 deserts, Paran is listed, but Kadesh is not, indicating that Kadesh was not considered a separate desert.
Kadesh is also described (33:36) as being in מדבר צין, but most suggest/assume that there was more than one Kadesh, so having the Kadesh the spies were sent from be in the Paran Desert and the Kadesh where Moshe hit the rock be in the Tzin Desert is not necessarily an issue. The Tzin Desert mentioned in 13:21 refers to part of the Promised Land that was scouted, so even though this desert included areas both inside and outside the land, the Kadesh the spies left from need not be in the Tzin Desert. Despite this, Yoel Elitzur (“Places in the Parsha,” Behaalotekha) posits that the Kadesh Desert and the Tzin Desert were both parts of the larger Paran Desert. That doesn’t impact the Sinai Desert being distinct from the Paran Desert, with the Sinai Desert covering the southern part of the Sinai Peninsula and the Paran Desert covering most of the peninsula to its north.
There are/were other deserts on the Sinai Peninsula as well. Northwest of the Sinai Desert is/was the Sin Desert (Shemos 16:1, Bamidbar 33:10-11), with four stops between מדבר סין and מדבר סיני (Bamidbar 33:11-15). [We know that the Sin Desert is/was northwest of the Sinai Desert because the nation was traveling south, close to the eastern bank of the Gulf of Suez.] In the upper northwest corner of the Sinai Peninsula,was the Shur Desert, where the nation emerged from the Red Sea after it split (Shemos 15:22). However, it’s also referred to as the Eisom Desert (Bamidbar 33:8). Here too, though, it is possible that this isn’t a proper name, but refers to “the desert that Eisom is in.” Bnei Yisroel had been at Eisom before they crossed the sea (33:6), and the Torah may be pointing out that they had already made it onto the Sinai Peninsula before turning back to trick Pharoah and lead him into the sea, emerging back on the peninsula after crossing it. Nevertheless, there may be another explanation for the name of this desert changing from מדבר שור to מדבר אתם.
One of the things that impressed Yisro was that “no slave had been able to escape from Egypt, as it was a closed land, [yet] 600,000 were able to leave” (Rashi, based on the Mechilta, on Shemos 18:9). Ancient Egypt was known for its fortresses, e.g. Tjaru on the major road between Egypt and Canaan, which prevented foreign attacks as well as slaves from getting out. As Itzhak Beit Arieh put it in the May/June 1988 issue of BAR (“The Road Through Sinai: Why the Israelites Fleeing Egypt Went South”), “he Egyptians had constructed a fortification line called ‘Shur Mitzrayim,’ the Wall of Egypt, to protect the Delta and to control the movement of nomads coming from the other side.” “Shur” means wall; the desert that was on the other side of this “wall of fortresses” was, therefore, called the Shur Desert. However, after this “wall” was breached during the Exodus, this name/description wasn’t valid anymore.
Whether that desert was no longer referred to as the Shur Desert by anyone, or the Torah no longer referred to it that way, when the מסעות (travels of Bnei Yisroel) were listed in the 40th year, it wasn’t called the Shur Desert, but the Eisom Desert. Either way, despite being on the Sinai Peninsula, it was not part of the Sinai Desert (מדבר סיני), which was limited to the southern part of the peninsula.
Rabbi Dov Kramer wrote a weekly D’var Torah from 5764-5776, most of which are archived at RabbiDMK.wordpress.com and AishDas.org/ta. His Jewish Geography pieces are available at dmkjewishgeography.wordpress.com; he wrote about the location of Mt. Sinai for Parashas Vayikra, and being in Eisom,both before and after crossing the sea, for Parashas Beshalach.
