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Bo 5773

By: Rav David Milston

Rashi’s opening comment to Sefer Bereishit identifies "Kiddush HaChodesh" – sanctifying each month, as the first mitzvah given to Am Yisrael as a nation.[1]


The Sefer HaChinuch seems to agree, even though he lists Rosh Chodesh as being the fourth commandment.[2]  


Why did the Almighty choose Kiddush HaChodesh as the first mitzvah to be given to Am Yisrael?


The Sefer HaChinuch writes:

"The wisest authorized Beit Din in the Land of Israel must sanctify months and intercalate years, and set the dates of the year's festivals according to that sanctification. For it is stated: ‘This month shall be the beginning of months for you.’ (Shemot 12:2)


When you see the renewal of the moon, you will establish the date as the beginning of the month. Even if you do not see it, but know it is due, the month will begin according to the accepted reckoning.


Two reputable Jews come before the Beit Din and testify they saw the moon in its renewal. The judges set the beginning of the month according to their word.”


This precept also includes the obligation to add a lunar month where necessary, making the year into a leap year.


Nowadays, we have the tradition that R. Hillel HaNassi (son of Rabbi Yehuda HaNassi) sanctified the months and intercalated the years until Eliyahu arrives to herald the advent of Mashiach.


The Sefer HaChinuch describes this mitzvah as a technical means of fixing the calendar. Later on in the Torah, we see Rosh Chodesh is not just a medium, but a somewhat festive day:


"Also in the days of your gladness, and in your appointed seasons, and in your new moons, you shall blow with the trumpets over your burnt-offerings and over the sacrifices of your peace-offerings and they shall be a memorial for you before your God: I am the Lord your God."[3]


Rosh Chodesh is categorized with “days of your gladness, and appointed seasons.” Furthermore, towards the end of Sefer Bamidbar, we are instructed to bring special sacrifices in honor of this first day of the month:


"And in your new moons you shall present a burnt-offering unto the Lord. Two young bullocks and one ram, seven he-lambs of the first year without blemish and three tenth parts of an ephah of fine flour for a meal offering, mingled with oil, for each bullock. And two tenth parts of fine flour for a meal offering, mingled with oil, for the one ram. And a several tenth part of fine flour mingled with oil for a meal offering unto every lamb, for a burnt offering of a sweet savor, an offering made by fire unto the Lord. And their drink offerings shall be half a hin of wine for a bullock, and the third part of a hin for the ram, and the fourth part of a hin for a lamb. This is the burnt offering of every New Moon throughout the months of the year. And one he-goat for a sin offering unto the Lord. It shall be offered beside the continual burnt offering and the drink offering." [4]


Sefer Shmuel mentions the custom of a festive seuda on Rosh Chodesh:


"So David hid himself in the field, and when the new moon came, the king sat down to eat the meal. And the king sat upon his seat, the seat by the wall as at other times, and Jonathan stood up, and Avner sat by Saul's side but David's place was empty. Nevertheless, Saul kept silent that day; for he thought, “something has befallen him, he is unclean; surely he is not clean.” And it came to pass on the day after the new moon, the second day that David's place was empty. And Saul said to Jonathan his son, “Why did the son of Jesse not attend the meals, neither yesterday nor today?” And Jonathan answered Saul, “David earnestly asked leave of me to go to Beit Lechem and he said, “Let me go, I pray you, for our family has a sacrifice in the city, and my brother has commanded me. And now, if I have found favor in your eyes, let me get away, I pray of you, and see my brothers. Therefore he has not come to the king's table.'"[5]


We also see here a possible allusion to the second day of Rosh Chodesh – “neither yesterday, nor today” – which occurred periodically depending on the lateness of the sighting of the new moon.[6]


Another reference appears in Sefer Melachim, in the episode of Elisha and the Shunamite woman. His prophecy about her bearing a child comes true, but the infant became severely ill whilst in the fields with his father. His mother decides to go to the prophet to beg for help and her husband (perhaps unaware of the initial prophecy and thus perplexed at his wife's reaction) remarks:


"…Why are you going to him today? It is neither New Moon nor Sabbath.” And she said, “It shall be well.'"[7]


We can therefore deduce that the new moon was a day when the people would visit their spiritual leaders.


So far, we have discovered two very different facets of Rosh Chodesh. First, as a technical necessity to fix the months of the Jewish calendar. No specific importance to the day itself but merely a marker for the more important days to follow. Indeed, the emphasis of the instruction is on events leading up to the declaration of the new month rather than the day itself.[8]


On the other hand, we see that Rosh Chodesh is a kind of semi-festival, a day for special sacrifices and festive meals yet with no official work prohibition, like Shabbat and Yom Tov. We also see that people dedicated at least a part of the day to visit their spiritual leaders.[9]


With this information in hand, let us return to our initial question. Why was Rosh Chodesh singled out as the first official mitzvah given to Am Yisrael?


Perhaps Rosh Chodesh defines Judaism’s religious infrastructure, with both its objectives and limitations.


Man was created in the image of God. Nothing reflects that more than our ability to make choices and determine who we are and what we do. However, one may expect a people about to become the Nation of God to be totally subservient with no allowance for self-determination or self-expression. Of course we know that is not true. Therefore the first mitzvah comes to categorically rebut such a philosophy.


The Almighty wants His people to fix their own calendar and run their own lives. They will look out for the new moon, go to Beit Din to testify, decide when a month begins and consequently determine the exact dates of the festivals.


Man has autonomy, even in the world of Halacha. Although God created and continues to create daily,[10] we have choice, which is a decisive factor in running the world. God sanctifies Israel and Israel defines time – “Mekadesh Yisrael VeHaZemanim.”


Can there be a more fundamental message? The very first of our national mitzvot defines God as the all powerful Creator and Man as the all powerful Chooser.


Let us take this a stage further. How does the Jewish calendar actually work?


We have established that the Jewish year is essentially lunar, yet we know that is not entirely accurate. Were our dates to be entirely lunar, our system would be extremely similar to the Moslem cycle. Just as the month of Ramadan moves freely from season to season, so too Pesach would sometimes fall in the winter and Sukkot in the spring.[11]  


To avoid this, the Torah does not allow any deviation from the seasons of the year.

For example, Pesach is not simply defined by a specific date, but by the spring.[12]Similarly, Sukkot is not only defined by a month and a day, but by the fall.[13]


So the Jewish yearly cycle is actually a combination of lunar and solar. Man determines the date through the former but the Almighty qualifies that date by defining the latter. What an incredible message to give this fledgling nation just as they are about to leaveEgypt and begin life as an independent people!  


We are to take the initiative in our lives and religious activities, but only within the parameters provided by Hashem.


As we approach each month, we are reminded of our potential and our limitations. The Beit Din will decide whether the testimony of the new moon is authentic, but it can only do so in relation to the sun, to the seasons of the year.


Our religious reality is made up of Am Yisrael who have been compared to the moon (see Midrash Tehillim Mizmor 22) and Torat Yisrael that has been compared to the sun (see Megillah 16b). What makes the moon shine? The sun! What distinguishes our nation from all other nations? Torah and God’s promise.


This explains why after playing our part in defining the new month as instructed by the Torah, we can celebrate our definition as a nation and as individual Jews. Every Rosh Chodesh, we are reminded of our potential and our limitations.


With that knowledge firmly embedded in our minds and hearts, the new month is sure to be full of blessing and abundant success.


Shabbat Shalom

Rav Milston

[1] See Shemot 12:2.

[2] The mitzvot of “Be fruitful and multiply,” circumcision and “Gid HaNasheh,” the prohibition of eating the sinew of the thigh, in Sefer Bereishit, were given to individuals – Adam, Avraham and Ya’akov respectively. They were only incorporated into the 613 Mitzvot later on, whereas Rosh Chodesh was the first mitzvah given to the nation as a whole.

[3] Bamidbar 10:10.

[4] 28:11-15.

[5] Shmuel Alef 20:24-29.

[6] A new moon appears approximately every 29.5 days. Sometimes Rosh Chodesh would be declared after 29 days, sometimes after 30. In a month that retrospectively turned out to be 30 days long, the status of the 30th day would remain unclear until the arrival or non-arrival of witnesses. Thus, the 30th day was often celebrated as Rosh Chodesh only to discover later that Rosh Chodesh was in fact the next day. In such cases, two days of Rosh Chodesh were celebrated. That is why we also have the custom of celebrating two days for certain months. However, even though we refer to these days as two days of Rosh Chodesh, it is only the second that is considered the first of the month.

[7] Melachim Bet 4:23.

[8] See the first two Mishnaic Chapters of Massechet Rosh HaShanah

[9] An additional source is the Mishna in Megillah 21a, where the importance of specific days is reflected by how many people are called up to the Torah on those days. Rosh Chodesh is categorized together with Chol HaMoed, when four people are called up as opposed to three on a regular weekday reading and five on a Yom Tov.

[10] Hence the determination of Shabbat remains with Him – “Mekadesh et HaShabbat.”

[11] There are 365 days in the solar year and 354 days in the lunar year. If we adopt a purely lunar system, we would lose 11 days for every year of the solar cycle. As the years go by, these days would naturally accumulate until what was once a summer celebration would become a winter festival.

[12] Shemot 23:15, 34:18, Devarim 15:1.

[13] Devarim 16:13.


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