And it came to pass on the eighth day
When the seven days of consecration were ended, as Ben Gersom, the day following them, so soon was Aaron called to the execution of his office; and so both the Targum of Jonathan and Jarchi make it to be the eighth day of the consecration, or the day after the anointing of Aaron and his sons, and which they both say was the beginning, or first day of Nisan, the day the tabernacle was erected by Moses: but that seems to have been set up before the consecration; rather this was, as Aben Ezra says, the eighth day of the month Nisan or March, and was the eighth day of the consecration, which began at the first day, on which day the tabernacle was set up, ( Exodus 40:2 ) :
[that] Moses, called Aaron and his sons, and the elders of Israel;
Aaron and his sons to enter upon their office, by offering sacrifices for themselves, and for the people, and the elders to be witnesses thereof.