one young bull, one ram, and one male lamb a year old for a burnt offering;
We have here an account of the great solemnity of dedicating the altars, both that of burnt-offerings and that of incense; they had been sanctified before, when they were anointed (Lev 8:10, Lev 8:11), but now they were handselled, as it were, by the princes, with their free-will offerings.
Commenting on Numbers 7:10-89
This was the dedication of the altar by the princes,.... These the presents they made, and the offerings they offered when the altar first began to be made use of, after it had been anointed and sanctified for sacred service: in the day when it was anointed: this shows that it was not the precise and exact day of the setting up of the tabernacle...
Num 7:12-88 All the princes brought the same gifts. The order in which the twelve princes, whose names have already been given at Num 1:5-15, made their presentation, corresponded to the order of the tribes in the camp (ch. 2), the tribe-prince of Judah taking the lead, and the prince of Naphtali coming last.
Commenting on Numbers 7:12-88