The First Commandment
Although the Hebrew calendar that we are familiar with is fixed and predictable, the original Hebrew calendar is dynamic and fluctuating. Every month, the Great Court decided when the month began―according to witnesses who testified that the moon had reappeared, and other criteria that were under its authority―and every few years they set a leap year. This method instills in us a constant sense of how time ticks on. Today, however, we use a calendar that was set following a system of rules, which draws its authority from the last Great Court that sanctified the months. So, we still have a calendar, and the Hebrew date still ticks away vibrantly, month after month and year after year.
In Hebrew the word “month” (חוֹדֶשׁ) is from the same root as “new” (חָדָשׁ), because the new moon, which marks the beginning of the month, is a symbol of renewal. It is not by chance that the word “month” (חוֹדֶשׁ) is similar to the word “sanctity” (קוֹדֶשׁ), as in the phrase, “sanctifying the month” (קִידוּשׁ הַחוֹדֶשׁ). It is also not by chance that we mention this commandment on the Shabbat before the month of Nisan, as a sign that something new is beginning. Because, this commandment is also the very first commandment that was given to the Jewish People as a nation, as the Exodus from Egypt approached. In fact, the sages ask why the Torah doesn’t begin with the verse, “This month is for you”―since it is the first commandment that the Jewish People were commanded to keep (whereas the commandments that were given to the Patriarchs, such as circumcision to Abraham, are obligatory to us only because we were once more commanded to keep it when we became a people at the Exodus). “Everything follows the beginning” and if this is the first commandment then it is obvious that this is not an individual commandment―just one of the 613 commandments―but a general commandment, the key that opens up the entire world of Torah and mitzvot (commandments).
Let’s note that this commandment is not phrased as a command, approaching us with a demand to do something in particular (as for example, in the following verses, “Speak to the entire Congregation of the Children of Israel… that they should take for themselves every man a lamb for their household”). Rather, it is a statement of fact, “This is the head of the months.” Just know that that is so. This type of language is familiar to us from the Ten Commandments which begin with the commandment, “I am Havayah your God…” a sentence that, on the one hand, is said as a statement of fact, but, on the other hand, also commands us (i.e., the commandment to believe in God). We can learn from this that we should relate to these two commandments―sanctifying the month and belief in God―as foundation stones in our lives: as Jews it is clear that we believe in God, “I am Havayah your God,” and it is clear to us that we have the commandment to sanctify the month, “This month is for you.”
Anyone confronted with the Hebrew calendar for the first time will come up against a simple question: What is the meaning of a double-headed year? On the one hand we have our familiar New Year (Rosh Hashanah) on the first of Tishrei, but on the other hand we have the “Head of the months” on the first of Nisan! Wouldn’t it be more logical for a new year to begin in the first month and not in the seventh month?!
The answer is found within the question itself. Indeed, literally speaking, the year begins with Tisrhei. One might say that the international, universal calendar begins with Tishrei. But, an upheaval occurred at the Exodus. God approached us in a special way and told us, “This month is the head of the months for you. It is the first month of the months of the year for you.” For you there is a new agenda. The New Year will continue to be in Tishrei, but from now you will count the months from Nisan, the month you were redeemed in, as Nachmanides explains:
This numeration is not for the year, since our years begin from Tishrei… So, when we call Nisan the first month and Tishrei the seventh, we are referring to the first month of redemption and the seventh month counting from it. This is the reason why “It is the first month of the months of the year for you” because although it is not the first of the year, it is the first month for you, called so to remind us of our redemption.
Rosh Hashanah in Tishrei marks the Creation of the World, “In Tishrei the world was created,” or, as we say in the Rosh Hashanah prayers, “This is the day of the beginning of Your acts.” By contrast, Nisan, as the first of the months, marks the Exodus from Egypt. At first glance, it is most appropriate to begin the year from the date of Creation, but we are obstinately different, as if for us, everything begins from the Exodus. Indeed, when the Almighty approached us at Mt. Sinai, He did not present His ID card as the Creator of the Universe. Instead, He began by saying, “I am Havayah your God who brought you out of the Land of Egypt.” This means that our Jewish identity begins with the Exodus from Egypt, and we relate first and foremost to God as He brought us out of Egypt and chose us to be His Chosen People. From this perspective, we return to Creation and also recognize God as the Creator of the entire universe. Havayah is our God, with whom we have a special, close relationship, after which He is the King of the entire world.
This can be understood better by looking at things through the prism of renewal. At the Exodus, we experienced a greater and more impressive sense of renewal than at creation. Although from a superficial perspective, there can be nothing newer than the innovation of creation ex-nihilo, “In the beginning, God created… and God said, ‘Let there be light!’ And there was light”―not just as a one-time event in the distant past, but at every moment He, “renews in His goodness every day always, the Working of Creation.” Nonetheless, as explained in Chassidut,  however this is a wondrous innovation, we perceive it at a relatively superficial level. Yes, I am created and renewed, like a newly born babe. But, there is a far deeper level of renewal, which is the renewal of the soul. Not only are we constantly reborn and renewed at the simple level of physical consciousness, but also at a far more profound level of Divine vitality that is constantly being renewed at the deepest strata of the soul. God approaches us as the one who brought us out of Egypt (מִצְרָיִם), because it is He who brings us out of all constraints (מְצָרִים)―even the physical constraints of the body―and renews our souls. This type of renewal is one that can never be achieved as long as we recognize God only as the Creator of the physical world. In other words, by “This month is for you” we reach a sense of genuine spiritual renewal and vitality. 
Let’s get back to the profound question of identity. In our times, we all carry our identity cards with us. However, in addition, everyone must answer to the question of “Who am I?” Do I identify myself as an individual with a unique name or by which “group” I belong to? There are some for whom this question isn’t of any concern to them at all, because they were born into an uncomplicated reality that they have never questioned. So too, the simple Jewish answer to the question of “Who are you?” throughout the generations has always been, “I am Jewish.” That’s a clear fact, even though I may not understand its significance.
But Jews in particular like to ask questions (remember the questions we ask on the Seder night?) and they also like to break all conventions and myths. That’s why you can find many Jews who have their doubts about the traditional reply, and try to find alternatives: I’m cosmopolitan, I am a human being, or I am an Israeli. In reality, this is a real dilemma: to what extent are we cosmopolitan, members of a great “family of nations,” and to what extent are we a special creation?
Apparently, the answer is clear-cut. A Jew is a “different breed” altogether. Without disparaging all other human beings on the face of the earth―we all descend from Adam who was created in the “image of God”―we have a unique “spiritual gene” that is branded into our souls. Just as God Himself presents His identity to us as the One who brought us out of Egypt, so we too perceive ourselves not as a part of humanity but as a nation with a unique identity and a special fate. When all is said and done, every Jew begins their day with the “provocative” statement, when he blesses God: “Who chose us from all of the nations and gave us His Torah.” The truth is, of course, that this statement is not intended to be provocative. This is our identity through which we have a special responsibility towards all of humanity, and if we deny it, we deny our very existence. The Jewish People is indeed, “extra-ordinary”―extracted from the ordinary nations to become something else.
To Teach the Ordinary
However, this is not the complete picture. So far, one might get the impression that we have completely left the world of the gentiles, saying, “Goodbye!” Beginning with Abraham who is called “Abraham the Hebrew [עִבְרִי]―because the whole world was on one side [עֵבֵר אֶחָד] and he was on the other side [מֵהָעֵבֵר הַשֵׁנִי].”
In truth, this is referring to a far more complex relationship between the Jews and the rest of the world. This is exemplified in the words of one of the great Chassidic masters, the author of the Sefat Emet, who explained that at first, the Jewish People was intermingled with the gentiles, but once Abraham came on the scene, a new nation with a unique identity began to crystallize, with whom God made a covenant (expressed in the circumcision of our bodies). But, Abraham did not lose hope in the world. He is referred to as “father of many nations” and he actively brought the world closer to the Almighty and taught them knowledge of God, awe and love, “And all of the families of the earth will be blessed through you.” Moreover, the uniqueness of the Jewish People teaches us something about the essence that is to be found in all the nations to some extent. Abraham stemmed from them and all of them therefore retain an attachment to him, as if in all humans there is a hidden “Abrahamic” point, the potential to become Jewish that was realized by Abraham and by his descendants. This essential point is reflected in the opinion that everyone has to convert and become “a son of Abraham.”
Returning to the Ordinary
So far so good, but once the Exodus from Egypt occurred, something different happened. Once the choice of the Jewish People was completed, something completely new began. We turned over a new leaf that begins with “This month is for you.” Then, the Jewish People stepped out on a new, independent path.
The Sefat Emet continues by saying that at first, the Jewish People was ordinary but at the Exodus from Egypt they became “extraordinary” and now they can no longer return to be like the ordinary nations. The gap has become too critical, and we can no longer measure them all by the same scale. We turned our backs on Pharaoh, King of Egypt, miraculously crossed the Red Sea and continued on our journey to Mt. Sinai, to experience a uniquely Jewish experience that can never be reproduced, with a calendar of our own, our own Torah and, it would seem, our own God (who we know in a way that no-one else can know). At this stage, it is difficult to see how the Jewish People can have any connection with the world at large. “East is east and west is west, and never the twain shall meet.”
However, in the end, something brings us back to meet up with the nations. The ability to do now return (after the Exodus) creates a renewed and more appropriate connection between Jews and gentiles. This doesn’t mean that we will surrender our uniqueness, God forbid, but that we will expose that essential point in the gentiles that receives its vitality from the Jewish People, and resurrect Abraham’s vision of bringing blessing to all the nations. This is Mashiach’s vision and goal. Mashiach is not just the redeemer of the Jewish People; he will bring blessing to the entire world: “For then I will turn the peoples into a clear language for all of them to call in the Name of God and to serve Him side by side.” Our long journey began with “This month is for you” (החדש הזה לכם) and concludes with Mashiach, the son of David (משיח בן דוד). Amazingly, both Hebrew expressions have the same numerical value!
From a series of classes given by Rabbi Ginsburgh in Shevat 5747
 We will add a reminder here of the importance of using the Hebrew date where possible, which is unique to us as Jews (also, from the aspect of Jewish law it is preferable to refrain from making use of the Gregorian date where possible).
 See Sefat Emet, Parashat Bo, 650, beginning, “This month is for you.”
 "Vitality” (חִיוּת), and “This month is for you” (הַחֹדֶשׁ הַזֶה לָכֶם) both equal 424.