Consecration of the altar of holocausts (Ex 29:35-29:37)

“Thus you shall do to Aaron and to his sons, just as I have commanded you.  Through seven days you shall ordain them.  Every day you shall offer a bull as a sin offering for atonement.  Also you shall offer a sin offering for the altar, when you make atonement for it.  You shall anoint it to consecrate it.  Seven days you shall make atonement for the altar, and consecrate it.  The altar shall be most holy.  Whatever touches the altar shall become holy.”

Everything takes 7 days, an important number.  Every day you take a bull and sacrifice it so that the altar itself can become holy, anointed, and consecrated.  Anointing is important in that is what consecrates it.  Who or whatever touches the altar shall become holy like the altar.