Leviticus 16:3

Thus shall Aaron come,—with a young bullock, &c.— Two solemn sacrifices were to be offered by the high-priest for himself and his family, (Leviticus 16:6.—in which family, some have thought, are included not only the priests, but the Levites also) preparatory to his entrance into the holy of holies: a sin-offering, in confession of his own weakness, and need of a better intercessor; see ch. Leviticus 4:3. Hebrews 7:27 and a burnt-offering, in token of his entire dedication of himself to God.