13 Take all the fat around the internal organs, the long lobe of the liver, and the two kidneys and the fat around them, and burn it all on the altar. 14 Then take the rest of the bull, including its hide, meat, and dung, and burn it outside the camp as a sin offering. 15 "Next Aaron and his sons must lay their hands on the head of one of the rams. 16 Then slaughter the ram, and splatter its blood against all sides of the altar. 17 Cut the ram into pieces, and wash off the internal organs and the legs. Set them alongside the head and the other pieces of the body, 18 then burn the entire animal on the altar. This is a burnt offering to the Lord ; it is a pleasing aroma, a special gift presented to the Lord . 19 "Now take the other ram, and have Aaron and his sons lay their hands on its head. 20 Then slaughter it, and apply some of its blood to the right earlobes of Aaron and his sons. Also put it on the thumbs of their right hands and the big toes of their right feet. Splatter the rest of the blood against all sides of the altar. 21 Then take some of the blood from the altar and some of the anointing oil, and sprinkle it on Aaron and his sons and on their garments. In this way, they and their garments will be set apart as holy. 22 "Since this is the ram for the ordination of Aaron and his sons, take the fat of the ram, including the fat of the broad tail, the fat around the internal organs, the long lobe of the liver, and the two kidneys and the fat around them, along with the right thigh.

Matthew Henry's Commentary on Exodus 29:13-22

Commentary on Exodus 29:1-37

(Read Exodus 29:1-37)

Aaron and his sons were to be set apart for the priest's office, with ceremony and solemnity. Our Lord Jesus is the great High Priest of our profession, called of God to be so; anointed with the Spirit, whence he is called Messiah, the Christ; clothed with glory and beauty; sanctified by his own blood; made perfect, or consecrated through sufferings, Matthew 12:28,) and by him the merit of Christ is applied to our souls. This consecration signifies the admission of a sinner into the spiritual priesthood, to offer spiritual sacrifices, acceptable to God through Jesus Christ.