This month [chodesh] will be for you the first month; it is the first month for you, of all of the months of the year.
This month will be for you rosh chodashim. While the simple reading of this verse is that this is the first month of the Jewish calendar, there is, as usual, another layer. The Sheloh writes that, in fact, this verse can also be read, “This month will be for you a month of Roshei Chodashim [the first day of the month], where every single day of the month is itself imbued with the power of Roshei Chodashim.
What is the meaning of this? What does it mean that the month of Nissan is a month of Roshei Chodashim? And why was this hinted to in the very first mitzvah that Hashem ever commanded the Jewish people?
David wrote, “The righteous one will flourish in his lifetime, with peace in abundance until there is no longer a moon.” The simple understanding of “until there is no longer a moon,” is that this is a poetic way of expressing “until the world no longer exists.”
Another explanation may lie in the particular Hebrew word used here for the moon, yareach. There are two words for “month” in the Hebrew language, one is yerach, and one is chodesh. When commenting on the verse, “On the third chodesh [month] after the children of Israel left Egypt…they arrived in the Sinai desert,” the Midrash comments, “It was the third chodesh, rather than the third yerach [another word for “month”] for, nischadshu bo dvarim, new things happened then.” The word chadash means “new,” and it is used to mean “month” because of the renewal of the moon each month. Thus, according to the Midrash, the word chodesh is used to mean “month” when there is re-invigoration and renewal. The great R. Chaim Palagi explains that this verse can be understood in the context of the Midrash; the righteous one will be productive and new and fresh and abundantly peaceful until he can no longer relate to the idea of yerach, but rather, he becomes a person of chodesh.
In fact, this theme appears once more in the laws of divorce. The Shulchan Aruch writes that when writing the date on a divorce document, one is to write, “this day on that yerach.” The Levush (R. Mordechai Joffe) says that this is hinted to in the verse where the tribe of Yosef is blessed by Moshe with “meged gerash yerachim,” literally, “the bounty of the moon’s yield,” for the word used for yield is gerash, which is also the word for divorce, and the word for moon is the word yerach. When it comes to a divorce, which is the unfortunate result of discord and absence of peace, then the word used is not that of chodesh, renewal, but rather, that of yerach. Thus, this passuk in Tehillim tells us that the future will carry such abundant peace that it will do away with “yerach.” In fact, there was once a custom to only hold weddings at times in the month when the moon was full! The Gemara asserts that the way to maintain a fresh love between husband and wife is to separate and then reunite in fulfillment of the Niddah laws. It was already understood in the times of the Gemara that the regular Niddah cycle is connected to the moon.
The moon is something that is a symbol of this world. It is something that is constantly in flux, waxing and waning. It has its ups and downs, as we all do. This can be something that is either perceived as depressing, making life seem endless and purposeless, or it can add great meaning to our lives. The waves of the ocean, with their ebb and drift, are also affected by the moon. Our relationships also have their ups and downs, but that is what makes them relationships. They cannot grow stale if we are ready to perceive the new moon as just that – renewal. It is precisely because there is a cycle that we can find newness and excitement in life. The peace that exists in life, and in relationships, is largely a product of seeing life’s ups and downs as chodesh. In marriage, we record in the kesubah and other documents which chodesh it happens in, and we look to the new moon. In divorce, unfortunately, we are in the stale mode of yareach. The righteous person is blessed that he will experience such peace that he will no longer live with any yareach at all.
Rosh Chodesh is fundamentally different from Shabbos, explains the Chiddushei Harim of Ger, for while Shabbos is the conclusion of the week, Rosh Chodesh comes first. The potential for the next month is there in the first day. It is the potential that we all get even before accomplishing anything, as opposed to the Shabbos experience, which is entirely dependent upon the quality of one’s week.
The month of Nissan is the month of freshness. It is the month when the Jewish people were chosen, and taken from slavery to freedom. The opinion of Rabbi Yehoshua, recorded in the Gemara, is that the world was created in Nissan. Chasam Sofer explains that this opinion means that the creation of the Jewish people was what made the world worthwhile, and therefore, the world was, so to speak, created in Nissan! It is a time when every day is once again the first day of the rest of your month – i.e., every day is packed with the potential to usher in a brand new reality. The very first message that the Jews received, in the first mitzvah that was given to them, was that today is a brand new day. There is a month that can teach you newness, that can remind you that there is always hope.
 Niddah 31b: “R. Meir said, ‘Why does the Torah mandate that a woman separate from her husband for seven days? Because her husband grows used to her, and not longer desires her as he did, so the Torah said, let her be impure for seven days so that she will be as beloved to her husband as she was to him when he first married her.’”
 See, in fact, Agra Dikallah to Pikudei (Vayikra 40:2), where he quotes the Rebbe of Lublin, that the first twelve days of Nissan have the potential for the entire year in them, each one corresponding to one month. He says that the Rebbe of Lublin would predict in writing some things that would happen that month in the coming year on each of these 12 days. He died in the month of Av, and that year, they found that he had only written up until the month of Av.