11 "Anyone who touches a dead body is ritually unclean for seven days. 12 He must purify himself with the Water-of-Cleansing on the third day; on the seventh day he will be clean. But if he doesn't follow the procedures for the third and seventh days, he won't be clean. 13 Anyone who touches the dead body of anyone and doesn't get cleansed desecrates God's Dwelling and is to be excommunicated. For as long as the Water-of-Cleansing has not been sprinkled on him, he remains ritually unclean. 14 "This is the rule for someone who dies in his tent: Anyone who enters the tent or is already in the tent is ritually unclean for seven days, 15 and every open container without a lid is unclean. 16 "Anyone out in the open field who touches a corpse, whether dead from violent or natural causes, or a human bone or a grave is unclean for seven days. 17 For this unclean person, take some ashes from the burned Absolution-Offering and add some fresh water to it in a bowl. 18 Find a ritually clean man to dip a sprig of hyssop into the water and sprinkle the tent and all its furnishings, the persons who were in the tent, the one who touched the bones of the person who was killed or died a natural death, and whoever may have touched a grave.
Matthew Henry's Commentary on Numbers 19:11-18
Commentary on Numbers 19:11-22
(Read Numbers 19:11-22)
Why did the law make a corpse a defiling thing? Because death is the wages of sin, which entered into the world by it, and reigns by the power of it. The law could not conquer death, nor abolish it, as the gospel does, by bringing life and immortality to light, and so introducing a better hope. As the ashes of the heifer signified the merit of Christ, so the running water signified the power and grace of the blessed Spirit, who is compared to rivers of living water; and it is by his work that the righteousness of Christ is applied to us for our cleansing. Those who promise themselves benefit by the righteousness of Christ, while they submit not to the grace and influence of the Holy Spirit, do but deceive themselves; we cannot be purified by the ashes, otherwise than in the running water. What use could there be in these appointments, if they do not refer to the doctrines concerning the sacrifice of Christ? But comparing them with the New Testament, the knowledge to be got from them is evident. The true state of fallen man is shown in these institutions. Here we learn the defiling nature of sin, and are warned to avoid evil communications.