This sugya discusses two different forms of counting the days of the Omer. The counting begins on the second day of Pesach (the day the Korban Omer was brought), and continues for seven weeks. There are two sources in the Torah for this mitzvah – one, a commandment to count 50 days, and the other, a commandment to count 7 weeks. The Gemara in Rosh Hashana tells us that this means that there are actually two different “counts” that we are commanded to perform.

There is a great dispute amongst the Rishonim if the mitzvah of Sefira today is only a Zecher l’Mikdash, since today there is no actual Korban Omer from which we can begin counting. But does this debate apply for both the counting of 50 days and the counting of seven weeks? (This dispute is covered in depth in our recent choveres Sefiras Ha’omer B’zeman Hazeh (click to view))

Among the questions discussed:

• Are they really two separate Mitzvos, or are they two parts of one greater Mitzvah (similar to Tefillin Shel Yad and Shel Rosh)?
• Is there a difference nowadays (that it is only Zecher lmikdash) between the “days” Mitzvah and the “weeks” Mitzvah?
• How is the counting of weeks performed? Are we obligated to count the week every day, or only as we complete each week?
• What if one forgets to count Sefira one night? May he still count with a Bracha since he still has the mitzvah to count weeks?