# Why are the days of sefiras haomer counted at the beginning but the weeks at the end?

When counting sefiras haomer, we count the number of the day we are about to start but the number of the week we have most recently completed. For example, on the first day we say "today is one day" even though we have not yet completed the first day as it is just starting. On the other hand, when we count weeks, we don't count a week until we reach the end (e.g. "today is seven days which are one week"). What is the reason for this inconsistency?

EDIT

To address the questions that have come up in the comments and answers so far, there are a number of ways the days and weeks could be counted consistently. For example, "Today is day 1, which is one day of the first week of the omer." Alternatively, as Double AA mentioned in comments, simply counting days and weeks separately: ״היום יום אחד לעומר. השבוע שבוע אחד לעומר״

• מקצת היום ככולו - once the day started it's like it already passed. Commented May 14, 2019 at 12:26
• I don't understand the question. Are you suggesting that we say שהם שבוע אחד from day one? Commented May 14, 2019 at 14:02
• @DonielF Well 1 day doesn't make 1 week, so probably not those exact words. But maybe something like "which is part of the first week" from day 1. Commented May 14, 2019 at 15:41
• @AlBerko I had considered that reasoning but couldn't find anything supporting it. Also, I wondered if the concept of ״מקצתו ככולו״ might apply to weeks as well. Commented May 14, 2019 at 15:58
• The Q is really good. We might say "today 5 days of week 1"! I think counting days is just הכי תמצי for counting the weeks that is mentioned in the Torah and that's the main goal of Omer (שבע שבתות תמימות). So days are secondary and can be counted all day. Commented May 14, 2019 at 16:07

I think the answer is closely related to understanding the answer to Why do we count Sefirah cardinally rather than ordinally?. In other words, we count the number of days that have passed since the beginning of the counting.

So, @AlBerko is on the right track here. The Judaic day begins at nightfall. Once that day has begun, we have to count, correct? We're not really looking at how much of that day has passed. We're just interested in the fact that a new day has begun, therefore, that's one more day to add to the count.

I would say to apply the same logic to the weeks. We're looking at how many weeks have passed since we started counting (i.e., cardinally). We're not looking at which week we are in. So, we wouldn't say on Day 1, "Today is 1 day, and we're in the first week." That doesn't match up with the time that has passed and been actually counted. Therefore, on Day 7, when truly a full week of days has actually been passed and counted, we say at that point, "today is 7 days which is 1 week."

• Why not say on day 1 "toweek is week 1"? (I know English doesn't have a word for 'the current week' but in Hebrew you can say השבוע just like היום) Commented May 14, 2019 at 13:31
• @DoubleAA Interesting idea. Have to ponder this..
– DanF
Commented May 14, 2019 at 13:33
• Why are we counting weeks that have passed instead of what week it is currently like we do for days? That's the whole question Commented May 14, 2019 at 15:48
• @Daniel I may be missing something in your question. Shulchan Aruch, I believe, states that in the same way that we count the days, so should we count the weeks. I.e., since we count the days that passed, we also count the weeks that have passed.
– DanF
Commented May 14, 2019 at 15:57
• @DanF That's talking about counting the days up rather than down. So we say "it's been 1 day of the omer" rather than "there are 48 days left of the omer". But we don't count full days that have already passed since we count them in the night, right as the day begins. Perhaps, as Al said in the comments on the OP it has something to do with ״מקצת היום ככולו״, but why don't we apply the same concept to the weeks? Commented May 14, 2019 at 15:59

I think we count the weeks the way we do since it's just less cumbersome being that we don't count the weeks as a total without details.

That is, we don't call the entire first week 'week one' and the entire second week 'week two'. As opposed to let's say years, when you (or the Torah) say a two year old cow, that leaves the question open, are we discussing a cow that finished two years since birth, or is it in it's second year. But either one is acceptable as far as language used.

Our count of weeks includes the fraction of the weeks, which gives a more accurate total. That is, the days besides the total weeks.

So imagine day eight: Today is day eight which is one week and one day as we do it, vs today is day eight which is two weeks less six days.

• But there are Rishonim who think you only need to count weeks on the whole-week days. This wouldn't answer for them Commented May 15, 2019 at 18:05
• @Double Do we have them stating how the counting of weeks would work? I.e. do they say at day eight start saying 8 days which is a week? (I don't recall offhand) Either way, our practice certainly makes more sense this way. Commented May 15, 2019 at 18:08
• I don't know, but the logically parallel way would be each day say היום יום פלוני at some point that day and each week say השבוע שבוע פלוני at some point that week. (Or only at night for some Rishonim) Commented May 15, 2019 at 18:15
• Curious. Truth is, according to the opinion that even when you miss a day you can still count weeks with a bracha by relying on those rishonim, we would be forced to say they counted weeks as completed, otherwise we would be counting the wrong weeks. But then, how to count the first week of Omer? Commented May 15, 2019 at 18:37

Maadanei Yom Tov says that we are counting days since the day commemorating Yetzi'as Mitzrayim. So that "hayom yom echad ba'omer" means one day elapsed since that moment in time, not that it is the first day. We are indeed counting "at the end" of one day, as you put it. Here is his argument:

Why is it that we celebrate Shuvu'os on the 6th of Sivan, and call it Zeman Matan Toraseinu -- the time of the giving of our Torah, when the Torah was actually given on the 7th?

Also, why is the Torah ambiguous about how many days to count? Quoting Vayiqra 23:15-16:

וּסְפַרְתֶּ֤ם לָכֶם֙ מִמָּחֳרַ֣ת הַשַּׁבָּ֔ת מִיּוֹם֙ הֲבִ֣יאֲכֶ֔ם אֶת־עֹ֖מֶר הַתְּנוּפָ֑ה שֶׁ֥בַע שַׁבָּת֖וֹת תְּמִימֹ֥ת תִּהְיֶֽינָה׃ עַ֣ד מִֽמָּחֳרַ֤ת הַשַּׁבָּת֙ הַשְּׁבִיעִ֔ת תִּסְפְּר֖וּ חֲמִשִּׁ֣ים י֑וֹם וְהִקְרַבְתֶּ֛ם מִנְחָ֥ה חֲדָשָׁ֖ה לַה׃

And from the day on which you bring the sheaf of elevation offering — the day after the day of rest — you shall count off seven weeks; they must be complete. You must count until the day after the seventh week — fifty days; then you shall bring an offering of new grain to Hashem.

Are we counting 7 weeks = 49 days, or 50 days? And while one might be tempted to say that Shavuos "the day after the seventh week" is the 50th day, what the verse actually says is to count 50 days until the day after the seventh week -- the weeks we were just talking about when we said 49. Not including it.

The answer is that we're counting from day 0. For us today, day 0 is the first day of Pesach. On the second day of Pesach we say "This is one day in/toward the omer" -- it's a day since day 0. And we would be bringing the qorban omer to mark the completion of 1 day, thus we count the time completed.

However, on the original Pesach, day 0 didn't begin at nightfall. The actual Exodus was during the day. And since (as per the quoted verse) omer has to count complete days and weeks, that meant their day 0 was on the second day of Pesach. They counted 49 days from that time, and thereby reached the 7th, not the 6th of Sivan.

So, we count a duration of 49 days, but because there is a 0th day, the last day of our count is a 50th day. Thus, both verses are fulfilled.

But, that means we are counting days from a t=0, and thus days too are "counted at the end" of the day.

• עד ממחרת השבת השביעית תספרו חמשים יום והקרבתם מנחה sounds like the holiday is on day 50 not 51. This is clever but hard to swallow Commented Apr 7, 2021 at 12:28
• He (and I /think/ it's the Tosafos Yom Tov, R YT Lipmann Heller) is saying that the pasuq isn't talking about "day 50" but "50 days after zeman cheiruseinu" or however it is he referred to day 0. "תספרו חמשים יום -- count 50 days" after, not "count to day 50". This is exactly why I thought MYT was talking about carinal vs ordinal. Commented Apr 8, 2021 at 13:06
• I'll say differently. Since it doesn't say עד ממחרת השבת השביעית תספרו חמשים יום ואחרי כן והקרבתם מנחה it sounds like there is a day that has three qualities: day after 7 weeks, 50-count, and holiday. According to this, 6 sivan has a holiday, and it has "count 50" since you count the number 50 even though it's the 51st relevant day, but I don't see how 6 sivan has "day after 7 weeks". The weeks contain days 0-6, 7-13 ... 42-48 which are counted on days after their conclusion 7, 14 ... 49 meaning מחרת השבת השביעית is 5 sivan. Commented Apr 8, 2021 at 13:22
• @DoubleAA, agreed. I just don't see it as more compelling than 50 days after. That is counting for 7 weeks of days -- because we don't measure 0 days after. Your hang up on "51st relevant day" is locking in to ordinal numbers -- as in the "st" of "51st". With cardinal numbers, and treating 0 as nothing, you get something that seems equally clear. BUT the MYT's version explains why our count ends one day earlier than the original year's count. Which was his whole reason for including the concept of 0 days after. (Your "1st day", but then, try to get out of the ordinals!) Commented Apr 8, 2021 at 19:31
• @DoubleAA, another way to think about your problem with "51st", bederekh mashal. When a boy is born on Shabbos, the beris is on the next Shabbos. Because beris milah works on ordinal numbers, "bayom hashemini -- on the 8th day". We are counting the baby's day 0, the one on which he was born. But we think of Shabbos as every 7th day because we don't count the day 0, the previous Shabbos. If you think of omer counting in that second way, there is no 51st, just 50 days after zeman cheiruseinu, measured by counting the 49 days before Shavuos: zeman chareiruseinu +1 day, ZC + 2 days, etc... Commented Apr 8, 2021 at 19:38