Reference for Keritot 4:14

תו הא דתנן

Now this is rendered possible if he became defiled on the seventh [clean] day<span class="x" onmousemove="('comment',' A nazirite who is defiled during the period of his naziriteship has to count seven clean days and bring an offering on the eighth day. He has then to observe again his vow of naziriteship for the period stipulated, v. Num. VI, 9f. If he is defiled on the seventh of the clean days, he has to start again this period of cleanness, etc.');">⁸</span>

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