Numbers 33:38

38And Aaron the priest went up aMount Hor at the command of the Lord and died there, in the fortieth year after the people of Israel had come out of the land of Egypt, on the first day of the fifth month.

Deuteronomy 1:3

3 bIn the fortieth year, on the first day of the eleventh month, Moses spoke to the people of Israel according to all that the Lord had given him in commandment to them,

Deuteronomy 2:14

14And the time from our leaving cKadesh-barnea until we crossed dthe brook Zered was thirty-eight years, euntil the entire generation, that is, the men of war, had perished from the camp, as the Lord had sworn to them.
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