20 You are to take some of its blood and put it on the four horns of the altar and on the four corners of the upper ledge and all around the rim, and so purify the altar and make atonement for it.

Read Ezekiel 43:20 Using Other Translations

And thou shalt take of the blood thereof, and put it on the four horns of it, and on the four corners of the settle, and upon the border round about: thus shalt thou cleanse and purge it.
And you shall take some of its blood and put it on the four horns of the altar and on the four corners of the ledge and upon the rim all around. Thus you shall purify the altar and make atonement for it.
You will take some of its blood and smear it on the four horns of the altar, the four corners of the upper ledge, and the curb that runs around that ledge. This will cleanse and make atonement for the altar.