Echad mi yodeia? Who knows One? Who knows two? Who knows seven?

A simple folk song? The commentators don’t think so.

Rav Pincus tells us to pay close attention to the lyrics. We don’t ask, “Who knows an example of seven?” We are not seeking models or illustrations of each number. Rather, we inquire, “Who knows seven?” We are seeking knowledge of the number itself. Who can define the energy and meaning of seven? The answer is: shivah yemei shabbata. The message of seven lies in the seven-day duration of the week.

In mathematics, seven is one of the important primary numbers (one through ten), which form the basis of our number system. At the same time, seven is unique within this group. It’s the largest prime number under ten, which means that it cannot be subdivided evenly (unlike, for example, the number nine, which can be split into three groups of three). At the same time, it’s also not a factor of any other number from one through ten (unlike the number five, which multiplies evenly into ten). Both these qualities indicate that seven is a distinctive, complete number that stands on its own.

Just as Hashem created the physical world, so did He create the concept of numbers, as well as the numbers themselves. The uniqueness of seven as a basic number in mathematics is a reflection of its uniqueness as a building block of creation.

The number seven figures largely in the story of Creation. The Vilna Gaon tells us that the Torah contains within it all the secrets of the universe and all the details of world history, and that all this information is encapsulated in the first pasuk of the Torah, which contains seven words, Bereishis bara Elokim es haShamayim v’es ha’aretz. And, of course, Creation itself consisted of six days climaxing in the seventh day of Shabbos.

Thus, explains Rav Hirsch (Collected Writings, Vol. 3), seven is a number denoting a full set, and it is used in numerous places in Tanach to express the full measure of something: Dovid praises Hashem seven times each day (Tehillim 119:164); a tzaddik falls seven times and rises again (Mishlei 24:16); Cain will be avenged twice sevenfold (Bereishis 4:15).

Seven as Culmination

Seven represents the concept of completion and wholeness, but there is yet another facet to the concept of seven. Here’s a brainteaser: What do the following names have in common: Chanoch, Moshe, Dovid?

The answer can be found in the Midrash Vayikra Rabbah (29:11) that tells us “kol hasheviin chavivin l’olam — all sevenths are forever beloved.” Among the many examples cited by Chazal are Chanoch, the seventh descendant of Adam Harishon; Moshe, the seventh generation from Avraham Avinu; and Dovid, seventh son of Yishai. Each of these is both the seventh and the most important of its group. Thus, in many sets of seven, the seventh item is the culmination of, and stands apart from, the first six.

In order to understand the full significance of the seventh in Hashem’s world, we must first understand the concept of six.

The Vilna Gaon notes that, just as the first verse of the Torah contains within it the entire world, so the first word of the Torah encapsulates the entire universe and all of world history. The word Bereishis consists of six letters plus the dagesh (dot) inside the letter beis. What is the significance of this dot, or point?

The Maharal explains that the number six represents the physical world, because a cube, the smallest unit of three-dimensional space, has six faces: four sides, the top and the bottom. But there is a seventh factor, albeit invisible, in the composition of a cube. Any six sides do not necessarily join together to form a cube. One can enter a room and find six boards scattered randomly in six different places, with no connection to each other at all. It is only when they are juxtaposed into a cubic shape that they form an integral unit. One way to express this structural unity is by identifying the central point in the core of the cube as a focal point that brings together all six components to form a whole. This center is what the Maharal calls the heichal hakodesh, the inner holy sanctum, the spiritual point — spiritual because it takes up no space, is intangible, and invisible, yet gives form, unity, and meaning to the six physical components.

So six represents physicality, and the seventh represents kedushas hachomer, the sanctification or purposefulness of that physicality. This relationship between six and seven applies not only to space, but also to time. The physical world was created in six days. It is the seventh day, however, that set the seal on Creation. On this day we reflect upon our Creator and our King. Shabbos is itself a day of meaning, but it also gives purpose and unity to the other six days.

As Rav Hirsch writes, the seventh day gave man “an awareness of the invisible Creator and Master… this awareness conferred upon each component of Creation its purpose and completion… the seventh day added the Invisible to the perceptible; it established the bond between the Creator and His creation, between the Master and His work, between G-d and His world.”

Not only does the seventh day give purpose to our days, it can also be regarded as the center of our week. Imagine a week without Shabbos. The six days would repeat themselves endlessly and would be indistinguishable from one another. Shabbos provides time with its familiar rhythm and unity: on Wednesday, Thursday, and Friday, we look ahead to the upcoming Shabbos; on Sunday, Monday, and Tuesday, we come away from the past Shabbos. The Gemara explains that one is allowed to make Havdalah up until Tuesday, for the first three days of the new week “belong” to the previous Shabbos. In this sense, Shabbos is the spiritual center, the heichal hakodesh, of the week.

In The Wisdom in the Hebrew Alphabet, Rabbi Michael Munk tells us that the letter zayin, which has a value of seven, is written in the sefer Torah with a curved top, facing forward and backward, to indicate that the radiant effect of Shabbos affects the last three days of the preceding week, and the first three days of the following week.

The dynamics of six plus one, or seven, represent the basic concept of our world: an observable, physical universe, with one invisible Creator — the center from which the entire universe emanates, the axis around which the entire world revolves, and the focal point toward which we all strive, no matter where we’re situated.

Rav Hirsch uses the seven lamps of the Menorah in the Beis Hamikdash as a symbol of the six/seven concept. In Torah thought, light is often used as a metaphor for chochmah. In Mishlei (9:1), we’re told that “wisdom has hewn out its seven pillars.” The seven lights of the Menorah represent complete illumination, or the sum total of knowledge. At the same time, however, one of the lamps stands apart. The Menorah was fashioned so that six lamps branched out from a central shaft. The central lamp shone upward toward the heavens, and the three lamps on each side faced toward the center. Thus, the center lamp was both the foundation and the culmination of the six. There is one Beginning and one Goal. All knowledge emanates from Hashem and all knowledge leads to Him.

The Maharal notes another property of seven: It is the exact midpoint of numbers four and ten, two other frequent and significant numbers in Jewish thought and practice. Four characterizes the physical world (the four directions of north, south, east, and west), and ten is a number that signifies the spiritual realm (the Aseres Hadibros, for example). Thus, seven is the interface, or meeting place, of the physical and the spiritual.

Pointing to the Purpose

From the very beginning of time, and from the very start of the Torah, the theme of six plus one, or seven, reminds us of the purpose of the universe, the goals of life, and the objectives of our personal existence. The concept of seven does not allow us to be so immersed in our material world that we forget the heichal hakodesh, the presence of Hashem at the center of our lives. As Rav Pincus puts it: The number seven is the number of kedushah; it’s Hashem’s seal upon Creation.

This is why so many mitzvos are related to the number seven. The mitzvos are physical acts that reverberate in the spiritual world. They elevate all elements of Olam Hazeh and infuse them with meaning. Rav Hirsch specifically addresses the mitzvos of Shabbos and shemittah when he writes: “By renouncing the physical world on the seventh day and renouncing the Jewish soil during the seventh year, we pay homage to the Invisible One, and so connect our six with the ‘Seven.’ ”

The Sefer Hachinuch writes about the mitzvah of shemittah: “…so that man will remember that the Land that gives forth its produce does not do so because of its nature. Rather, there is a Master over the Land and its owners, and when He wishes, He commands us to disclaim it.”

One of the common denominators of Shabbos and shemittah is relinquishment — of control, of ownership, of self. On Shabbos, we refrain from melachah, creative work, deferring to Hashem as the Creator and the King of the universe. During shemittah, we refrain from agricultural activities, conveying homage to Hashem as the Master and Owner of the Land.

How does the farmer find the courage to stop working every seventh year and allow his crops to become hefker, ownerless, and free for the taking? Similarly, what is the hardworking businessman thinking when he closes his shop each seventh day or is unable to clinch the lucrative deal before candlelighting?

Rav Chaim Friedlander explains that one who believes that Hashem is the true Sustainer will not have difficulty ceasing his work, for he knows that it’s not his own efforts that bring in parnassah; he merely goes through the motions and Hashem makes it happen. Thus Shabbos and shemittah develop and deepen our emunah and bitachon in a world where it is all too easy to overdo our quest for bread and materialistic success.

The Slonimer Rebbe links these two mitzvos in a number of ways. The phrase “Shabbos l’Hashem” is used in the Torah to describe both Shabbos and shemittah, indicating that both these mitzvos present an unparalleled opportunity to extricate ourselves from the mundane and devote time to spiritual pursuits. One of the roots of the word Shabbos is shuv, to return. The seventh unit, the “beloved seven,” returns our focus to the Center and reminds us of the ultimate purpose of life.

Just as Shabbos is the mekor habrachah, the source of blessing for the entire week, infusing the world with energy for the next seven days, similarly, the shemittah year confers brachah on Eretz Yisrael for the entire seven-year cycle. Pirkei Avos tells us that the punishment for violating shemittah is galus. Successful existence in Eretz Yisrael is dependent on this mitzvah.

Rabbi Munk writes that the word zayin, seven, is a derivative of zon — nourishment and sustenance, and is also related to klei zayin — arms and weaponry. When we relinquish control and hand the reins over to Hashem during the seventh year, we are ensured of His care and protection.

The Slonimer Rebbe points out that while Shabbos is sourced in the beginning of Creation, shemittah is linked to its culmination. We’re told that the Geulah will come b’motzaei shiviis, in the aftermath of the shemittah year. Furthermore, the era of Mashiach in the seventh millennium can be regarded as the “shemittah” of world history, as it will culminate 6,000 years of the world’s existence and herald a time of spiritual return and refocus. May we merit to see Hashem accelerate this timetable for us, speedily in our days!

Parts of this essay are based on the writings of Rav Moshe Shapiro.

Mrs. Shani Mendlowitz is a teacher at Bais Yaakov Seminary in Montreal, and is a popular adult lecturer.

(Originally featured in Family First, Issue 412)