Numbers 19:5 (BSB)

Then the heifer must be burned in his sight. Its hide, its flesh, and its blood are to be burned, along with its dung.

From Numbers 19. Also in the ESV.

Commentary on Numbers 19:5

• Matthew Henry (Presbyterian), Matthew Henry's Complete Commentary on Numbers 19:1-10: We have here the divine appointment concerning the solemn burning of a red heifer to ashes, and the preserving of the ashes, that of them might be made, not a beautifying, but a purifying, water, for that was the utmost the law reached to; it offered not to adorn as the gospel does, but to cleanse only.
• John Gill (Reformed Baptist), Exposition of the Old and New Testaments on Numbers 19:5: And one shall burn the heifer in his sight,.... Another priest, as the Targum of Jonathan, Eleazar looking on, as that expresses it; the Jews say (g), that when the priest came to the mount of Olives, accompanied by the elders of Israel, before he burnt the cow, he dipped himself in a dipping place there; and the wood being laid there in order, wood...
• Keil & Delitzsch (Lutheran), Biblical Commentary on the Old Testament on Numbers 19:2-10: Num 19:2-10 Preparation of the Purifying Water. - As water is the ordinary means by which all kinds of uncleanness are removed, it was also to be employed in the removal of the uncleanness of death. But as this uncleanness was the strongest of all religious defilements, fresh water alone was not sufficient to remove it; and consequently a certain kind of sprinkling-water was appointed...