And the pure person shall sprinkle upon the unclean on the third day and on the seventh day, and shall purify him on the seventh day; and he shall wash his clothes and bathe in water and be pure at evening.
English: Why say “on the third day and on the seventh day”? It was needed: you might have thought the third excludes the second and the seventh excludes the sixth when one shortens the days of purity, but if one did the third and the eighth, lengthening the days, it would be fine — therefore the verse teaches otherwise.
Type of Learning
Exclusion of alternate day-counts.
What Is Learned
The sprinklings must fall specifically on day three and day seven of the count.