This section begins with, “In the first month…,” which is referring to the first month (Abib, or Nisan) in the spring of the 40th year in the wilderness. The documentation in the book of Numbers, as with the rest of the Bible, leaves the majority of the years of wandering without a detailed record. We assume the people moved annually through a similar series of locations and stops that depended on the seasonal conditions. Numbers 33:2-49 records the general campsites through the forty years and this campsite in Numbers 20:1 at Kadesh in the Desert of Zin at the end of the 40 years correlates with Numbers 33:36.
After forty years of wandering in the wilderness Israel goes again to the Desert of Zin on the east side of the wilderness and they camp at Kadesh (called ‘Ain Qedeis today) where forty years earlier (Numbers 13-14) the people had rebelled by refusing to enter the Promised Land. Kadesh is about fifty miles southwest of Beersheba, a city of Abraham.
As the forty years of punishment comes to an end so are the lives of all those who were 20 years old or older at the time of the nation’s rebellion and refusal to enter the Promised Land. Mariam, Moses’ older sister, dies in the first month or at the beginning of this fortieth year while they were camped at Kadesh. (Aaron will die 4-5 months later at the end of Numbers (20:22-29). Aaron’s death is also recorded Numbers 33:38 as being “on the first day of the fifth month of the 40th year after the Israelites came out of Egypt.”) Mariam would be one of the last of her rebellious generation to die before Israel would begin to make their second approach towards the Promised Land.
Kadesh was normally a well-watered oasis at this time of year, but during the spring of Israel’s fortieth year Kadesh was dry. The springs at this oasis produce 1,400 cubic feet of water per hour. When Israel arrives and finds this oasis dry the second generation begins to complain with the same voice and similar logic of their parents who had complained in an comparable situation forty years earlier (Exodus 17:7).