Numbers 4:27

Overview - Numbers 4
The age at which the Levites were to begin to serve, and the duration of the service.
The duty of the Kohathites.
16 The charge of Eleazar.
17 The office of the priests.
21 The duty of the Gershonites;
29 of the Merarites.
34 The number of the Kohathites;
38 of the Gershonites
42 and of the Merarites.
Treasury of Scripture Knowledge

Numbers 4:27  (King James Version)
At the appointment of Aaron and his sons shall be all the service of the sons of the Gershonites, in all their burdens, and in all their service: and ye shall appoint unto them in charge all their burdens.

Hebrew mouth.
The Levites were under the command of the priests. Eleazar exercised this authority in general, as next in succession to Aaron: and he in particular was placed over the Kohathites; while Ithamar, his younger brother, commanded the Gershonites and Merarites
(ver. 33.)
Luke 1:70 ; 1 Corinthians 11:2