'Purification' in the Bible

But the meat of the bull, its skin, and its dung you are to burn up outside the camp. It is the purification offering.

Every day you are to prepare a bull for a purification offering for atonement. You are to purge the altar by making atonement for it, and you are to anoint it to set it apart as holy.

“Once a year Aaron is to perform the purification rite on the horns of the altar. Throughout your generations he is to perform the purification rite for it once a year, with the blood of the sin offering for atonement. The altar is especially holy to the Lord.”