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Section: Parshas HaShavua   Category: Quick Vort
Parshas Tazria: Daas Zikeinim - No Choice But To Lock Him Up For Seven Days

If a person comes to a Kohen with a Nega that meets certain criteria, but has no sure signs of Tumah, the Kohen quarantines him for seven days and then checks back again to see if it spread. Why does the Kohen wait seven days? Is he too busy for a daily checkup?

The Daas Zikeinim answers that the slow spread of a tzoraas would not be noticeable day by day. Only over a full week can you see a noticeable difference, and even then only if you don't check each day. We find the same thing by the Mabul when Noach sent out a bird only every seven days.

"Why not just put a marker around the Nega to see if it grows?" ask the Daas Zikeinim. "Markers can be erased and rewritten. Unlike by hair where a row of hairs is left around the nega as a border to see if it spread."