You must take some of its blood and put it on the four horns of it, and on the four corners of the ledge and on the border all around; thus you will cleanse it and make atonement for it. Bible other translations

“and make atonement for it.” Before the altar could be regularly used for sacrifice it had to be cleansed and made holy. This was also done for the altar in Moses’ Tabernacle (cp. Lev 16:18).

Commentary for: Ezekiel 43:20