Numbers 20:23-28

23And the  Lord said to Moses and Aaron at Mount Hor, on the border of the land of Edom, 24 a  “Let Aaron be gathered to his people, for he shall not enter the land that I have given to the people of Israel, because b  you rebelled against my command at the waters of Meribah. 25Take Aaron and Eleazar his son and bring them up to Mount Hor. 26And strip Aaron of his garments and put them on Eleazar his son. And Aaron c  shall be gathered to his people and shall die there.” 27Moses did as the  Lord commanded. And they went up Mount Hor in the sight of all the congregation. 28 d  And Moses stripped Aaron of his garments and put them on Eleazar his son. And Aaron died there e  on the top of the mountain. Then Moses and Eleazar came down from the mountain.

Numbers 33:38

38And Aaron the priest went up f  Mount 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.
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