Ezekiel 43:25-27

Every day for seven days you shall prepare a goat for a sin offering; they shall also prepare a young bull and a ram from the flock, both without blemish. Seven days they shall make atonement for the altar and purify it, and so consecrate it. When these days are over it shall be, on the eighth day and thereafter, that the priests shall offer your burnt offerings and your peace offerings on the altar; and I will accept you,’ says the Lord GOD.”