He shall cleanse himself with the water on the third day and on the seventh day, and so be clean: The Hebrew verb rendered cleanse himself is the same one translated “purified themselves from sin” in 8.21 (see the comments there). Here it may be rendered “make himself ritually pure.” With the water is literally “with it” (New Jewish Publication Society’s Tanakh, Bijbel: Vertaling in opdracht van het Nederlandsch Bijbelgenootschap). Good News Translation says “with the water of purification.” Since the Hebrew word for “water” is plural and the Hebrew word for “ashes” is singular, strictly speaking the pronoun “it” refers to the ashes, which were kept outside the camp (verse 9). Contemporary Russian Version and Alter translate this phrase as “with the ashes,” which is in itself more accurate. However, it is clear from verse 9 that the ashes mixed with water would serve as the prescribed cleansing agent to rid people of ritual contamination. For this reason the most helpful model here is the one in Contemporary English Version, which is “with the water mixed with the cow’s ashes.” The Hebrew verb rendered be clean may be translated “be ritually clean.”

But if he does not cleanse himself on the third day and on the seventh day, he will not become clean: But renders well the Hebrew waw conjunction (literally “and”), which introduces a contrast here. The previous sentence gives the purifying instructions in positive terms, but here they are expressed again in negative terms, thus emphasizing them.

Quoted with permission from de Regt, Lénart J. and Wendland, Ernst R. A Handbook on Numbers. (UBS Helps for Translators). Miami: UBS, 2016. For this and other handbooks for translators see here .