1 sn In the last chapter the needs of the priests and Levites were addressed. Now the concern is for the people. This provision from the sacrifice of the red heifer is a precaution to ensure that the purity of the tabernacle was not violated by pollutions of impurity or death. This chapter has two main parts, both dealing with ceremonial purity: the ritual of the red heifer (vv. 1-10), and the purification from uncleanness (vv. 11-22). For further study see J. Milgrom, “The Paradox of the Red Cow (Num 19),” VT 31 (1981): 62-72.
