Numbers 16:38 (BSB)

As for the censers of those who sinned at the cost of their own lives, hammer them into sheets to overlay the altar, for these were presented before the LORD, and so have become holy. They will serve as a sign to the Israelites.”

From Numbers 16. Also in the ESV.

Commentary on Numbers 16:38

• Matthew Henry (Presbyterian), Matthew Henry's Complete Commentary on Numbers 16:35-40: We must now look back to the door of the tabernacle, where we left the pretenders to the priesthood with their censers in their hands ready to offer incense; and here we find, I. Vengeance taken on them, Num 16:35.
• John Gill (Reformed Baptist), Exposition of the Old and New Testaments on Numbers 16:38: The censers of these sinners against their own souls,.... Who by burning incense in them sinned, and by sinning hurt and ruined their souls: let them make them broad plates for a covering of the altar; the altar of burnt offering, which, though it had a covering of brass, another made of these were to be over it, for the further security of it, being...
• Geneva Bible Notes (Reformed), Geneva Bible Study Notes on Numbers 16:38: The censers of these sinners against their own souls, let them make them broad plates [for] a covering of the altar: for they offered them before the LORD, therefore they are hallowed: and they shall be a sign unto the children of Israel. (o) Who caused their own death. (p) Of God's judgments against rebels.
• Keil & Delitzsch (Lutheran), Biblical Commentary on the Old Testament on Numbers 16:36-40: Num 16:36-40 (Or Hebrew_Bible_17:1-5). After the destruction of the sinners, the Lord commanded that Eleazar should take up the censers “from between the burning,” i.e., from the midst of the men that had been burned, and scatter the fire (the burning coals in the pans) far away, that it might not be used any more.