Albert Barnes Commentary Ezekiel 43:22

"And on the second day thou shalt offer a he-goat without blemish for a sin-offering; and they shall cleanse the altar, as they did cleanse it with the bullock." — Ezekiel 43:22 (ASV)

They shall cleanse - By sprinkling the blood (Ezekiel 43:18). Here “they” marks the act as that of the priests. Moses did his part before the priests were consecrated, and the seer could act through them.