Numbers 19:21, commentary and pictures

The verse belongs to the red-heifer ordinance, which points to Christ. It requires the one who sprinkles the water of separation to wash his clothes, and anyone who touches that water is unclean until evening. The Hebrew word used is nah-zah, meaning sprinkle, a sense preserved in the English and Greek renderings, not immersion. It belongs to ritual cleansing for bodily defilement rather than atonement for sin, and it is an exception to the typical rule that purification was by blood.

Although described as perpetual and forever, its duration is limited by the nature and circumstances of the ceremonial ordinance, which was abolished at the death of Christ. As a perpetual statute it is an example of a law meant to continue after Israel entered the promised land, unlike the temporary wilderness prohibition on kindling fires.

The same ashes mingled with water cleanse the unclean person while the clean person who sprinkles them becomes unclean until evening and must wash his clothes, as also happened with the priest who sprinkled the red heifer's blood and the one who gathered her ashes. Two lives are represented in the sin offering, the innocent life of the victim and the imputed sinful life of the offerer, so its blood conveys defilement to the sanctuary while at the same time cleansing the sinner. The verse typifies Christ on the cross made sin and suffering as the vilest of sinners, yet by virtue of His own pure life cleansing sinners at the same time, as when He cleansed the thief.

The sprinkling sanctified to the cleanness of the flesh as the type of the blood of Christ cleansing the conscience from dead works. The red-heifer sacrifice was performed once for all for the whole people, yet it did not give indiscriminate purification, since each defiled person had to individually lay hold of the provision to be freed from personal impurity, so Christ tasting death for all still requires each person singly to appropriate what He did for all. The sprinkling of the ashes did not take place in the second apartment, the holy of holies, and its place in the argument of Hebrews 9 shows that the ministry in the heavenly sanctuary as a whole includes the holy place and not the most holy place alone. The verse is part of the ceremonial law given to Israel as a code of health laws whose spirit opposes superstitious practices such as pressing the lips against the dead, which spreads disease such as tuberculosis.