1 Chronicles 24:19
This was the order in which they carried out their assigned responsibilities when they entered the Lord's temple, according to the regulations given them by their ancestor Aaron, just as the Lord God of Israel had instructed him.
1 Chronicles 9:25
Their relatives, who lived in their settlements, came from time to time and served with them for seven-day periods.
1 Chronicles 24:1
The divisions of Aaron's descendants were as follows: The sons of Aaron: Nadab, Abihu, Eleazar, and Ithamar.
2 Chronicles 23:4
This is what you must do. One third of you priests and Levites who are on duty during the Sabbath will guard the doors.
2 Chronicles 23:8
The Levites and all the men of Judah did just as Jehoiada the priest ordered. Each of them took his men, those who were on duty during the Sabbath as well as those who were off duty on the Sabbath. Jehoiada the priest did not release his divisions from their duties.
1 Corinthians 14:40
And do everything in a decent and orderly manner.
Hebrews 7:11
So if perfection had in fact been possible through the Levitical priesthood -- for on that basis the people received the law -- what further need would there have been for another priest to arise, said to be in the order of Melchizedek and not in Aaron's order?