The case for Jebel Musa and St. Catherine’s Monastery as Biblical Mount Sinai largely rests on the age of the tradition identifying it as such.
Eastern Roman Emperor Justinian founded St. Catherine’s Monastery to honor the mountain as the “Mountain of Moses” (Jebel Musa) in 527 AD. Since that time, Jebel Musa has held most people’s belief that it is Mount Sinai.
Dr. Graham Davies of Cambridge University believes that the early Jewish pilgrimages identified Jebel Musa as Mount Sinai, and that later Christian pilgrims adopted this tradition. Old Testament scholar R.K. Harrison stated in the Bible Encyclopedia that “Jebel Musa . . . seems to have enjoyed special sanctity long before Christian times, culminating in its identification with Mt. Sinai.”
We asked Dr. Thomas Williams, professor of theology at Regina Apostolorum Pontifical Athenaeum in Rome, and he wrote back with his assessment of why Mount Sinai would be located in the southern part of Egypt’s Sinai Peninsula.
Several factors suggest the Israelites fled southward into Sinai and that Mount Sinai should be located in the southern sector of the peninsula. First, Exodus 13:17 warned against travel by the “way of the land of the Philistines.” This route, which hugged the northern coast, was the major military route used by the pharaohs and was heavily garrisoned. As part of the great trunk route—the International Coastal Highway—this road would be watched closely by the Egyptians. Second, Deuteronomy 1:2 locates Mount Sinai as an eleven-day journey from Kadesh-barnea, a note that fits best with a Mount Sinai located somewhere in the southern peninsula. Third, the Israelites lost the exact location of Mount Sinai after 850 b.c. when Elijah fled to the holy mountain.
Had the holy mountain been located in the more frequented regions of the north, surely its location would be remembered. Finally, a few sites mentioned on the journey from Mount Sinai to Kadesh-barnea suggest a southern route if the several tentative identifications are plausible. For example, Dizahab (Deut. 1:1) arguably is modern Dahab located on the southeastern coast of the Sinai. Jotbathah (Num. 33:33) may be identified with the Oasis of Taba a few miles south of Ezion-geber (Tell el-Kheleifeh). The following discussion presumes a location for Mount Sinai somewhere in the southern part of the peninsula.
Some supporters of this traditional candidate have pointed to an area where the Golden Calf was allegedly placed.
According to British Egyptologist David M. Rohl, the chapel of Harun (the Biblical name of Aaron) is located at the head of the valley where the Monastery is located, and is right at the start of the route up the slopes of Jebel Musa.
Also nearby, to the northwest, is a small shrine upon a hill which proponents believe is the spot upon which Moses stood as the Israelites battled the Amalekites on their way to Mount Sinai.
Supporters of this traditional designation argue that it is compatible with the information provided by the famous 1st century Jewish historian, Josephus. One particular piece of information, which would be required by the criteria, does play in Jebel Musa’s favor as Mount Sinai.
The historian Josephus wrote that Mount Sinai was the highest mountain in the region and that its slopes were particularly difficult to ascend. The cluster of mountains by St. Catherine’s Monastery, which includes Jebel Musa and Mt. Catherine, is easily the highest range of mountains in the Sinai Peninsula. It also has what Justinian believed to be the descendant of the Burning Bush, around which the monastery was built.
Egyptologist David Rohl
Dr. Graham Davies of Cambridge University
Dr. Thomas Williams, professor of theology at Regina Apostolorum Pontifical Athenaeum in Rome
 Graham I. Davies, Society for Old Testament Study Monographs, vol. 5, The Way of the Wilderness: a Geographical Study of the Wilderness Itineraries in the Old Testament (Cambridge: Cambridge University Press, 1979), 23-24.
 David M. Rohl, Exodus: Myth or History? (St. Louis Park, MN: Thinking Man Media, 2015), 229.