Albert Barnes Commentary Numbers 16:46

"And Moses said unto Aaron, Take they censer, and put fire therein from off the altar, and lay incense thereon, and carry it quickly unto the congregation, and make atonement for them: for there is wrath gone out from Jehovah; the plague is begun." — Numbers 16:46 (ASV)

A censer—Rather, the censer. That is, that of the high priest which was used by him on the great Day of Atonement: compare Leviticus 16:12; Hebrews 9:4.