We learned on yesterday’s daf of a disagreement between Rav Matana and bar Pada regarding the source of the idea that stam nezirut sheloshim yom – the standard length of nezirut is 30 days. Based on their different readings of the words of the Torah, only Rav Matana really believes that nezirut is 30 days; bar Pada concludes that the standard length of nezirut is 29 days. How does bar Pada – an amora – explain the clear ruling of the Mishna, which requires 30 days?
Our Gemara explains that bar Pada interprets the 30th day as referring to the day after nezriut when the concluding sacrifices are brought and the nazir shaves his hair.
In explaining the Mishna‘s teaching (see 16a) that a nazir shaves his hair on the 31st day, but that if he shaved on the 30th day he has fulfilled his obligation, Rav Matana says that standard practice is to wait until the full 30 days are over, but that the concept of miktzat ha-yom ke-kulo – that we count part of the day as a whole day – would allow the nazir to shave even on the 30th day. Bar Pada, on the other hand, does not accept the idea of miktzat ha-yom ke-kulo. He suggests that the standard practice would allow the nazir to shave on the 30th day (since minimum nezirut is only 29 days), but that the Sages ruled that we add a rabbinic day on to the standard nezirut. The Rosh explains that since many people say round numbers – something we even find in the Torah, where the traditional 39 lashes are referred to as 40, or the 49-day count of sefirat ha-Omer from Pesaḥ to Shavuot is called the 50-day counting – it was viewed as prudent to add an extra day to the standard nezirut. Nevertheless, if a person were to shave on the 30th day, he would fulfill his biblical obligation and his nezirut would be complete.