When Moses approached Aaron with the news of God's commission to appoint him as high priest, Aaron said: "What! Thou hadst all the labor of erecting the Tabernacle, and I am now to be its high priest!" But Moses replied: "As truly as thou livest, although thou art to be high priest, I am as happy as if I had been chosen myself. As thou didst rejoice in my elevation, so do I now rejoice in thine."
Moses continued: "My brother Aaron, although God had become reconciled to Israel and has forgiven them their sin, still, through thy offering must thou close the mouth of Satan, that he may not hate thee when thou enterest the sanctuary. Take then a young calf as a sin-offering, for as thou didst nearly lose thy claim to the dignity of high priest through a calf, so shalt thou now through the sacrifice of a calf be established in thy dignity."
Then Moses turned to the people, saying: "You have two sins to atone for: the selling of Joseph, whose coat you fathers smeared with the blood of a kid to convince their father that its owner had been torn to pieces by a wild beast, and the sin you committed through the worship of the Golden Calf. Take, then, a kid to atone for the guilt you brought upon yourselves with a kid, and take a calf to atone for the sin you committed through a calf.
But to make sure that God had become reconciled to you, offer up a bull also, and thereby acknowledge that you are slaughtering before God your idol, the bull that you had erstwhile worshipped." The people, however, said to Moses: "What avails it this nation to do homage to its king, who is invisible?" Moses replied: "For this very reason did God command you to offer these sacrifices, so that He may show Himself to you."
At these words they rejoiced greatly, for through them they knew that God was now completely reconciled to them, and they hastened to bring the offerings to the sanctuary. Moses admonished them with the words: "See to it now that you drive evil impulse from your hearts, that you now have but one thought and one resolution, to serve God; and that your undivided services are devoted singly and solely to the one God, for He is the God of gods and the Lord of lords. If you will act according to my words, 'the glory of the Lord shall appear unto you.'"