Albert Barnes Commentary Leviticus 8:3

"and assemble thou all the congregation at the door of the tent of meeting." — Leviticus 8:3 (ASV)

Gather ... - Rather, gather all the assembly together toward the entrance of the tent of meeting. See Leviticus 4:13. The whole body of the people were summoned on this occasion, and the elders probably occupied the first places.

The elders are especially called together in an unequivocal manner to receive directions to provide the first sacrifices for the nation, to be offered by the newly consecrated priests (Leviticus 9:1), and the body of the people afterward assemble as they do here (Leviticus 9:5).

The spot designated was the portion of the court in front of the tabernacle (see Leviticus 1:3 note). Toward this space, the people were commanded to assemble to witness the great national ceremony of the consecration of the priesthood.

This was the solemn setting apart of one of their families, whose members were from then on to stand as mediators between them and Yahweh in carrying out the precepts of the ceremonial law.

Those who could do so, may have come into the court, and a great number of others may have occupied the heights which overlooked the enclosure of the court. As the series of ceremonies was repeated every day for a week (Leviticus 8:33), it is natural to suppose that some of the people attended on one day and some on another.