Aaron: Age of, at Death
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Exodus 7:7
Moses was eighty years old and Aaron was eighty-three when they spoke to Pharaoh.
Numbers 33:38, 39
At the LORD’s command, Aaron the priest climbed Mount Hor and died there on the first day of the fifth month, in the fortieth year after the Israelites had come out of the land of Egypt. / Aaron was 123 years old when he died on Mount Hor.