Exodus 29:12, 36

And you shall take some of the blood of the bull and with your finger put it on the horns of the altar [of burnt offering], and you shall pour out the remainder of the blood at the base of the altar.

You shall offer a bull every day as a sin offering for atonement. You shall cleanse the altar from sin when you make atonement for it, and you shall anoint it to consecrate it [for God’s sacred purpose].